BOOK VI

Throughout this last Book, Gilbert glories in the Copernican theory,

the open, unquestioned, advocacy and endorsement of which according

to many seems, after all, to have been the object of the work. He

maintains that the magnetic axis of the earth remains invariable; he

treats of the daily magnetic revolution of the globes, as against the

time-honoured opinion of a _primum mobile_, the fixed stars being

at different distances from the earth; of the circular motion of the

earth and of its primary magnetic nature, whereby her poles are made

different from the poles of the ecliptic, as well as of the precession

of the equinoxes and of the obliquity of the zodiac.

According to Humboldt,[37] Gilbert was the first to make use of the

words _electric_ force, _electric_ emanations, _electric_ attraction,

but, he says, there is not found in “De Magnete” either the abstract

expression _electricitas_ or the barbarous word _magnetismus_

introduced in the seventeenth century. We likewise owe to Gilbert

the words _equator_, _magneticum_, _terrella_, _versorium_ and

_verticitas_, but not the word _pole_, which had before been used by P.

Peregrinus and others.

The second edition of “De Magnete” appeared at Stettin in 1628,

“embellished with a curious title-page in the form of a monument ...

and a fantastic indication of the earliest European mariner’s compass,

a floated lodestone, but floating in a bowl on the sea and left behind

by the ship sailing away from it.”[38]

The third edition was also published at Stettin during 1633. Gilbert

left, besides, a posthumous work, “De Mundo Nostro Sublunari

Philosophia Nova,” Amsterdam, 1651, which latter, says Prof. Robison,

consists of an attempt to establish a new system of natural philosophy

upon the ruins of the Aristotelian doctrine.[39]

To give here such an analysis as Gilbert’s admirable work merits would

be impracticable, but the short review of it made by Prof. Robison

(at p. 209 of his “System of Mechanical Philosophy,” London, 1822)

deserves full reproduction, as follows: “In the introduction, he

recounts all the knowledge of the ancients on the subject treated, and

their supine inattention to what was so entirely in their hands, and

the impossibility of ever adding to the stock of useful knowledge,

so long as men imagined themselves to be philosophizing, while they

were only repeating a few cant words and the unmeaning phrases of the

Aristotelian school. It is curious to mark the almost perfect sameness

of Dr. Gilbert’s sentiments and language with those of Lord Bacon. They

both charge, in a peremptory manner, all those who pretend to inform

others, to give over their dialectic labours, which are nothing but

ringing changes on a few trite truths, and many unfounded conjectures,

and immediately to betake themselves to experiment. He has pursued

this method on the subject of magnetism, with wonderful ardour, and

with equal genius and success; for Dr. Gilbert was possessed both

of great ingenuity, and a mind fitted for general views of things.

The work contains a prodigious number and variety of experiments and

observations, collected with sagacity from the writings of others, and

instituted by himself with considerable expense and labour. It would,

indeed, be a miracle if all of Dr. Gilbert’s general inferences were

just, or all his experiments accurate. It was untrodden ground. But,

on the whole, this performance contains more real information than

any writing of the age in which he lived, and is scarcely exceeded

by any that has appeared since. We may hold it with justice as the

first fruits of the Baconian or experimental philosophy.” Elsewhere,

Prof. Robison remarks: “It is not saying too much of this work to

affirm that it contains almost everything we know of magnetism. His

unwearied diligence in searching every writing on the subject and in

getting information from navigators, and his incessant occupation in

experiments, have left very few facts unknown to him. We meet with many

things in the writings of posterior inquirers, some of them of high

reputation and of the present day, which are published and received as

notable discoveries, but are contained in the rich collection of Dr.

Gilbert.”

The Rev. Wm. Whewell says in his “History of the Inductive Sciences”

(Vol. III. p. 49) that in the “De Magnete,” a book of only 240 pages,

upon which Dr. Gilbert has been engaged for nearly eighteen years, are

contained “all the fundamental facts of the science, so fully examined,

indeed, that, even at this day, we have little to add to them.”

Dr. John Davy remarks (“Memoirs of the Life of Sir Humphry Davy,”

London, 1836, Vol. I. p. 309): “Gilbert’s work is worthy being

studied, and I am surprised that an English Edition (translation)

of it has never been published.” He also alludes to the well-known

reproach thrown upon Gilbert’s philosophy by Francis Bacon, who, in

his “De Augmentis Scientiarum,” observes that “Gilbert has attempted

to raise a general system upon the magnet, endeavouring to build a

ship out of materials not sufficient to make the rowing-pins of a

boat.” On the other hand, Digby and Barlowe place Gilbert upon a level

with Harvey, Galileo, Gassendi and Descartes (“Nouvelle Biographie

Générale,” 1858, Vol. VIII. p. 494) while the celebrated historian

of the Council of Trent, Fra Paolo Sarpi--who will not be thought an

incompetent judge--names Gilbert, with Francis Vieta (the greatest

French mathematician of the sixteenth century) as the only original

writer among his contemporaries (“Lettere di Fra Paolo,” p. 31; Hallam,

“Intro. to Lit.,” 1859, Vol. II. p. 464).

In Thos. Thomson’s “History of the Royal Society,” London, 1812, the

“De Magnete” is thus alluded to: “Dr. Gilbert’s book on magnetism,

published in 1600, is one of the finest examples of inductive

philosophy that has ever been presented to the world. It is the more

remarkable because it preceded the ‘Novum Organum’ of Bacon, in which

the inductive method of philosophizing was first explained.” How far

Gilbert was ahead of his time is best proven by the works of those

who wrote on magnetism during the first few decades after his death.

They contributed in reality nothing to the extension of this branch of

physical science. Poggendorff, from whose “Geschichte der Physik,” p.

286, this is extracted, as already stated, calls Gilbert “the Galileo

of Magnetism.” By Dr. Priestley, he was named “the Father of Modern

Electricity.”

The tribute of Henry Hallam is to the following effect: “The year 1600

was the first in which England produced a remarkable work in physical

science; but this was one sufficient to raise a lasting reputation for

its author. Gilbert, a physician, in his Latin treatise on the magnet,

not only collected all the knowledge which others had possessed on the

subject, but became at once the father of experimental philosophy in

this island, and, by a singular felicity and acuteness of genius, the

founder of theories which have been revived after a lapse of ages, and

are almost universally received into the creed of science. Gilbert was

one of the earliest Copernicans, at least as to the rotation of the

earth, and, with his usual sagacity, inferred, before the invention of

the telescope, that there are a multitude of fixed stars beyond the

reach of our vision” (“Introduction to the Literature of the Fifteenth,

Sixteenth and Seventeenth Centuries,” London, 1859, Vol. II. p. 463).

In the “Principal Navigations ...” Edinburgh, 1889, Vol. XII. p. 10,

Richard Hakluyt speaks of “... my worshipfull friend M. douctour

Gilbert, a gentleman no lesse excellent in the chiefest secrets of the

Mathematicks (as that rare iewel lately set forth by him in Latine

doeth euidently declare) then in his oune profession of physicke.”

We conclude this account of Gilbert in the quaint words of old Dr.

Fuller: “He has (said my informer[40]) the _clearness of Venice Glass_

without the _Brittleness_ thereof, soon _Ripe_ and long _lasting_ is

his Perfection. He commenced _Doctor_ in _Physick_, and was _Physician_

to Queen _Elizabeth_, who stamped on him many marks of her Favour,

besides an annuall Pension to encourage his studies. He addicted

himself to _Chemistry_, attaining to great exactness therein. One saith

of him that he was _Stoicall_, but not _Cynicall_, which I understand

_Reserved_; but not _Morose_, never married, purposely to be more

beneficial to his brethren. Such his _Loyalty_ to the Queen that, as

if unwilling to survive, he dyed in the same year with her, 1603. His

_Stature_ was _Tall_, Complexion Chearful, an Happiness not ordinary in

so hard a student and so retired a person. He lyeth buried in _Trinity

Church_ in Colchester under a plain monument.”

“_Mahomet’s Tombe_, at Mecha, is said strangely to _hang_ up, attracted

by some invisible _Loadstone_, but the memory of this _Doctor_ will

never fall to the ground, which his incomparable book ‘De Magnete’

will _support_ to eternity” (“The History of the Worthies of England

Endeavoured by Thomas Fuller, D.D.,” London, 1662, p. 332--Essex).

In his Epistle to Dr. Walter Charleton, physician in ordinary to King

Charles I (Epist. III. p. 15, Vol. XI of the Works of Dryden, London,

1803) the celebrated English poet predicts that:

“_Gilbert shall live till loadstones cease to draw

Or British fleets the boundless ocean awe._”

REFERENCES.--“La Grande Encyclopédie,” Vol. XVIII. p. 930;

“Dictionary of National Biography,” London, 1890, Vol. XXI. p.

338; “Bibliographica Britannica,” London, 1757, Vol. IV. p.

2202; Larousse, “Dict. Univ.,” Vol. VIII. p. 123; “Freeman’s

Historic Towns” (Colchester), by Rev. E. L. Cutts, 1888, p.

172; “Beauties of England and Wales,” by E. W. Brayley and

John Britton, 1810, Vol. V. (Colchester) pp. 318–319; Cooper,

“Athenæ Cantabrigienses,” Cambridge, 1858; Anthony à Wood,

“Athenæ Oxonienses,” London, 1813, Vol. I; Thomas Wright, “Hist.

and Top. of the County of Essex,” 1866, Vol. I; “Journal des

Savants” for June 1859, Sept. 1870; Wm. Munk, “The Roll of

the Royal College of Physicians of London,” 1878, Vol. I. p.

77; Humboldt, “Cosmos,” 1859–1860, Vol. I. pp. 158–159, note,

177, 179, 182, note; Vol. II. pp. xvii, 279–281, 334–335,

341–342; Vol. V. p. 58 for references to and extracts from Dr.

Gilbert’s work; Wm. Whewell, “Hist. of the Ind. Sciences,” Vol.

I. pp. 274–275, 394; Vol. II. pp. 192, 217–220, 224, 225, and

“Philosophy of the Ind. Sciences,” London, 1840, Vol. II. pp.

374–379; “Mémoires de Physique,” Lausanne, 1754, pp. 123, etc.;

“U.S. Magnetic Tables and Isogonic Charts for 1902,” L. A.

Bauer, pp. 1–77; “Popular Science Monthly,” August 1901, pp.

337–350 for “Gilbert of Colchester,” by Bro. _Potamian_, also

its translation in “Ciel et Terre” for Dec. 1, 1902, pp. 472–480

and for Dec. 16, 1902, p. 489; “New International Encyclopædia,”

New York, 1903, Vol. VIII. p. 368; “William Gilbert of

Colchester,” by Conrad Wm. Cooke, London, 1890 (reprinted from

“Engineering,” 1889); “William Gilbert of Colchester,” by

Dr. Silvanus P. Thompson, London, 1891; “William Gilbert of

Colchester,” a translation by P. Fleury Mottelay, New York and

London, 1893; “William Gilbert of Colchester,” a translation by

members of the Gilbert Club, London, 1900, to which is appended

a valuable collection of “Notes on the _De Magnete_” of Dr.

William Gilbert, by Dr. Silvanus P. Thompson, who therein also

gives an interesting bibliography of this great work; “William

Gilbert of Colchester,” a sketch of his magnetic philosophy

by Chas. E. Benham, Colchester, 1902; “Zur bibliographie von

W. Gilbert’s _De Magnete_,” Von. G. Hellmann (“Terrestrial

Magnetism and Atmospheric Electricity” for June 1902); “Terr.

Magn. and Atm. Elect.,” Vol. II. p. 45 for “The Earth a Great

Magnet,” by J. A. Fleming; “The Earth a Great Magnet,” by

Prof. Alfred M. Mayer, New York, 1872; Philip Morant, “History

and Antiquities of Colchester,” London, 1748; Bacon, “Novum

Organum,” Leyden, 1650, pp. 263–265; Rees’ “Encyclopædia,”

1819, Vol. XVI. article “Gilbert”; “A Course of Lectures on

Natural Philosophy and the Mechanical Arts,” by Thos. Young,

London, 1807, Vol. I. pp. 686, 747, 756; Vol. II. pp. 111,

324, 436; “Critical Dictionary of Engl. Literature,” S. Austin

Allibone, Philad., 1888, Vol. I. p. 668; “General Biographical

Dictionary,” John Gorton, London, 1833, Vol. II, mentioning

Wood’s “Athen. Ox.,” Hutchinson’s “Biog.-Med.,” and Aikin’s “G.

Biography”; _Phil. Trans._ for 1667, Vol. II. pp. 527–531, also

Baddam’s abridgments, London, 1739, Vol. III. p. 129 and London,

1745, Vol. I. p. 97.

=A.D. 1601.=--Brahé (Tycho--Tygge--Thyghe--Tyge), who has been several

times mentioned in this compilation and is referred to by Gilbert

(“De Magnete,” Book IV. chap. xii. also Book VI. chap. v.), was a

distinguished Danish astronomer (_b._ 1546, _d._ 1601), the founder

of modern astronomical calculations, whose investigations and records

of the positions of the stars and planets made possible the brilliant

discoveries of Kepler and Newton. As Humboldt expresses it, the rich

abundance of accurate observations furnished by Tycho Brahé, himself

the zealous opponent of the Copernican system, laid the foundation

for the discovery of those eternal laws of planetary movements which

prepared imperishable renown for the name of Kepler, and which,

interpreted by Newton, proved to be theoretically and necessarily

true, have been now transferred into the bright and glorious domain of

thought as _the intellectual recognition of nature_ (“Cosmos,” 1860,

Vol. II. p. 313).

As his very able biographer, Dr. J. L. E. Dreyer, of the Armagh

Observatory, remarks in his admirable work (Edinburgh, 1890): “Without

Brahé, Kepler never could have found out the secrets of the planetary

motions, and, in the words of Delambre, ‘Nous ignorerions peut être

encore le véritable système du monde.’ The most important inheritance

which Tycho left to Kepler and to posterity was the vast mass of

observations all which, Kepler justly said, ‘deserved to be kept

among the royal treasures, as the reform of astronomy could not be

accomplished without them ...’ at one breath blowing away the epicycles

and other musty appendages which disfigured the Copernican system....

Tycho Brahé had given Kepler the place to stand on and Kepler did move

the world!”

Brahé was the first to recognize the variation, _i. e._ the

inequality, in the moon’s motion. In opposition to the opinion of

Sédillot, M. Biot maintains that this fine discovery of Tycho by no

means belongs to Abul-Wefa, and that the latter was acquainted not

with the “variation” but only with the second part of the “evection”

(“Cosmos,” 1860, Vol. II. p. 222, wherein are many references to the

_Comptes Rendus_ and to the “Journal des Savants”).

The biographical division of the “English Cyclopædia,” 1866, Vol. I.

pp. 898–903, gives a list of Brahé’s numerous writings, headed by his

earliest publication, “De Nova Stella,” 1573, which is so extremely

rare that, until 1890, when Dr. Dreyer gave a description of it, not

a single historian of astronomy had ever seen it or been able to even

give its title correctly (“Journal of Br. Astron. Assoc.,” Vol. XII.

No. 2, p. 95; Houzeau et Lancaster, Vol. II. p. 598). A detailed

account of its contents is given at pp. 44–56 of Dr. Dreyer’s 1890

work above alluded to, wherein we are further told of the protection

given Brahé by the Landgrave William of Hesse-Cassel, as well as of the

consequent aid so liberally extended by King Frederick II. Reference

is likewise made to the fact that in December 1584 the King turned

to Tycho for help, writing that he was under the impression he had

returned a compass made by Tycho, believing there was something wrong

with it; that, if this proved to be the case, Tycho was to send back

the compass, but, if not, he was to make two new ones similar to the

old one (F. R. Friis, “Tyge Brahé,” p. 147).

REFERENCES.--“Life of Tycho Brahé,” by Gassendi, containing the

“Oratio Funebris,” etc., of John Jessenius; Tessier “Eloges

des hommes illustres,” Vol. IV. p. 383; Blount, “Censura,”

etc.; “Epistolæ ad Joh. Keplerum,” 1718; Riccioli, “Chronicon

in Almagesto Novo,” Vol. I. p. 46; the biography by Malte-Brun

in the “Biog. Univ.,” wherein is to be found the list of all

of Tycho Brahé’s writings; “English Cycl.,” Supplement to

Biography, p. 376, at Scipione Chiaromonti, for “Anti-Tycho”;

“Bulletin de la Société Astronomique de France,” Janvier 1903;

“Journal des Savants,” Juin 1864; Humboldt, “Cosmos,” 1860,

Vol. III. pp. 158, 160, 162; “Nature” of Dec. 27, 1900, p. 206,

and “Nature,” Vol. LXV. pp. 5–9, 104–106, 181, as well as the

“Bulletin Astronomique,” Paris, Avril 1902, pp. 163–166, for

account of the celebrations of the Tercentenary of Tycho-Brahé’s

death, held at Prague and elsewhere, on Oct. 24, 1901, with

illustrations of his observatory, etc. etc.; “Geschichte der

Mathem. von Abraham G. Kästner,” Vol. II. pp. 376, etc., 613,

etc.; R. A. Proctor, “Old and New Astronomy,” 1892 _passim_;

“Biog. Génér.,” 1890, Vol. XLV. pp. 750, 755; “La Grande

Encycl.,” Vol. VII. pp. 962–963; Larousse, “Dict. Univ.,” Vol.

XV. pp. 613–614; “Encycl. Brit.,” Edin., 1876, Vol. IV. p. 200.

Consult likewise for Abul Wefa: “Le Journal des Savants,” for

Nov. 1841, Sept. 1843, Mar. 1845 and Oct. 1871; Houzeau et

Lancaster, “Bibliog. Gén.,” 1887, Vol. I. pp. 598–600, and Vol.

II. pp. 92–93; “Bull. de la Soc. Acad. de Laon,” Janvier 1903,

pp. 40–48; Leopold Von Ranke, “History of England,” Vol. I. p.

367 and notes; Wm. Whewell, “Phil. of the Ind. Sc.,” London,

1840, Vol. II. pp. 386–388; Harold Höffding, “A Hist. of Mod.

Phil.,” translated by B. E. Mayer, London, 1900, Vol. I. p. 428.

=A.D. 1602.=--Blundeville (Thomas) publishes at London, “The

Theoriques of the Seuen Planets,” etc., which, as the lengthy title

goes to show, indicates “the making, description and vse of two

ingenious and necessarie instruments for sea men to find out thereby

the latitude of any place upon the sea or land, in the darkest night,

that is, without the helpe of sunne, moone or starre; first invented by

M. Dr. Gilbert, a most excellent philosopher, and one of the ordinarie

physicians to Her Majestie.”

He had previously published, in 1589, “A briefe description of

universal mappes and cardes and of their use; and also the use of

Ptolemy his Tables,” which was followed, during 1594, by his well-known

work on navigation. From the rare sixth edition of the latter (London,

1622) the curious title page is worth reproducing as follows: “M.

Blundeville, His Exercises, contayning eight treatises, the titles

whereof are set down in the next printed page: which treatises are

very necessary to be read and learned of all Young Gentlemen that

haue not beene exercised in such Disciplines and yet are desirous to

haue knowledge as well in Cosmographie, Astronomie and Geographie,

as also in the art of navigation, in which art it is impossible, to

profit without the helpe of these or such like Instructions. To the

furtherance of which Art of Navigation the sayd Master Blundeville

especially wrote the said Treatises and of meere good will doth

dedicate the same to all Young Gentlemen of this Realme.” The contents

of this curious work treat of Arithmetic, Cosmography, Terrestrial and

Celestial Globes, Peter Plancius, his Universal Map, Mr. Blagrau, his

Astrolabe, The First Principles of Navigation, etc. etc.

The Mr. Blagrau here mentioned is John Blagrave, eminent English

mathematician, author of “The Mathematical Jewel,” as well as of “The

making and use of the familiar staffe,” of “The Art of Dialling,” and

of “Astrolabium Uranicum Generale, a necessary and pleasunt solace and

recreation for Navigators in their long journeying, containing the use

of an instrument or astrolabe.” From the last named, it appears that

Blagrave was a convert to the heliocentric theory of Copernicus (“New

Gen. Biog. Dict.,” by Rev. H. J. Rose, London, 1850, Vol. IV. p. 277).

The invention of the dipping needle by Mr. Blagrave was before the

discovery of the change of the needle’s variation by Mr. Gellibrand

(“Philos. Britan.,” Benj. Martin, London, 1771, Vol. I. p. 46).

REFERENCES.--“Gen. Biogr. Dict.” (Gorton), London, 1833, Vol. I;

Hutton’s abridgments of the _Phil. Trans._, London, 1739, Vol.

IV. p. 103; “Dict. of Nat. Biog.,” Leslie Stephen, London, 1886,

Vol. V. pp. 157 and 271–272; “Gen. Biog. Dict.,” Alex. Chalmers,

London, 1812, Vol. V. pp. 370–371; “Biog. Univ.,” Paris, 1843,

Vol. IV. p. 397; “Nouv. Biog. Générale” (Hœfer), Paris, 1853,

pp. 170–171; Baddam’s abridgments of the _Phil. Trans._, London,

1739, Vol. IV. p. 103; “Ames’ Typog. Antiq.” (Herbert), pp. 693,

694, 697–701; Bloomfield’s “Norfolk,” Vol. LXIV. pp. 68–70;

Cooper’s “Athenæ Cantab.”; Davy’s “Suffolk Coll.,” Vol. LXXXIX.

p. 215; Hazlitt, “Coll. and Notes,” 1876, also the second series.

=A.D. 1609.=--Kepler (Johann), who succeeded Tycho Brahé in 1601

as astronomer to the German Emperor Rudolph II, is the author of a

treatise “On the Magnet,” which was followed, during 1609, by his

greatest work, the “Astronomia Nova.” The latter was deemed by Lalande

of such importance that he considered it the duty of every astronomer

to read it from beginning to end at least once in his lifetime.

The “Astronomia” contains the extraordinary book “on the motion of

Mars,” and is said to hold the intermediate place, besides being the

connecting link between the discoveries of Copernicus and those of

Newton. Kepler’s doctrine is thus enunciated by Dr. Whewell (“Physical

Astronomy,” Chap. I): “A certain Force or Virtue resides in the sun

by which all bodies within his influence are carried around him.

He illustrates (‘De Stella Martis,’ Chap. XXXIV. p. 3) the nature

of this Virtue in various ways, comparing it to Light and to the

Magnetic Power, which it resembles in the circumstances of operating

at a distance, and also in exercising a feebler influence as the

distance becomes greater.” In the Table of Contents of the work on the

planet Mars, the purport of the chapter to which allusion has been

made is stated as follows: “A Physical speculation, in which it is

demonstrated that the vehicle of that virtue which urges the planets,

circulates through the spaces of the universe after the manner of a

river or whirlpool (vortex), moving quicker than the planets.” It will

doubtless be found by any one who reads Kepler’s phrases concerning

the _moving force_--the _magnetic nature_--the _immaterial virtue_

of the sun, that they convey no distinct conception, except so far

as they are interpreted by the expressions here quoted: “A vortex of

fluid constantly whirling around the sun, kept in this whirling motion

by the rotation of the sun himself and carrying the planets around

the sun by its revolution, as a whirlpool carries straws, could be

readily understood; and though it appears to have been held by Kepler

that this current and vortex was immaterial, he ascribes to it the

power of overcoming the inertia of bodies, and of putting them and

keeping them in motion, the only material properties with which he had

anything to do. Kepler’s physical reasonings, therefore amount, in

fact, to the doctrine of vortices around the central bodies and are

occasionally so stated by himself; though by asserting these vortices

to be ‘an immaterial species,’ and by the fickleness and variety of his

phraseology on the subject, he leaves his theory in some confusion; a

proceeding, indeed, which both his want of sound mechanical conceptions

and his busy and inventive fancy might have led us to expect. Nor, we

may venture to say, was it easy for any one at Kepler’s time to devise

a more plausible theory than the theory of vortices might have been

made. It was only with the formation and progress of the science of

mechanics that this theory became untenable.”

REFERENCES.--“Kepler, sa vie et ses ouvrages,” in the “Journal

des Savants” for June, July and August 1847; Kepler’s

manuscripts, “Phil. Trans.,” Vol. XI. p. 27; Wm. Whewell, “Phil.

of the Ind. Sc.,” London, 1840, Vol. II. pp. 383–386; “Epistolæ

ad J. Keplerum,” published by M. G. Hansch in 1718; Houzeau

et Lancaster, “Bibliogr. Générale,” 1887, Vol. I. part i. pp.

612–614, detailing the contents of Kepler’s “Opera Omnia,” also

Vol. I. part ii. pp. 1315–1316, 1330–1331, 1383, and Vol. II.

pp. 175–176, 456–462 and 1581; Robert Small, “An Account of the

Astronomical Discoveries of Kepler,” London, 1804; Humboldt,

“Cosmos,” 1860, Vol. II. p. 710, notes, for Laplace, Chasles

and Brewster on the writings and theories of Kepler; “Jour.

des Savants” for June, July and August 1847; “Geschichte der

Mathem.,” Vol. III. p. 318, and Vol. IV. pp. 216, 311; Dr. Geo.

Miller, “Hist. Phil. Ill.,” London, 1849, Vol. III. notes at pp.

134–135; Fourth Dissert. of “Encycl. Brit.”; Whewell, “Hist. of

the Ind. Sc.,” 1859, Vol. I. pp. 291–311, 320, 386, 387, 415,

462, 532–534, and Vol. II. pp. 55, 56.

It will be well to look at the last-named work of Dr. Whewell for

references to Jeremiah Horrox--Horrockes--(1619–1641), the celebrated

young English scientist, who wrote in defence of the Copernican opinion

in his “Keplerian Astronomy defended and promoted” (“Hist. of the

Ind. Sc.,” Vol. I. Book V. chap. iii. p. 276, and Chap. V. p. 303),

as well as for references to Giovanni Alfonso Borelli (1608–1679).

Borelli, who has by many been erroneously called a pupil of Galileo,

was a distinguished Italian physicist and astronomer, born at Naples

in 1608, who founded what has been called the iatromathematical

school, which, under the protection of Leopold of Tuscany, became

known as the Accademia del Cimento. Whewell speaks of him in Vol. I.

at Book VI. chap. ii. p. 323, at Book VII. chap i. pp. 387, 393, 394,

and at Chap. II. pp. 303, 395, 405, 406. Horrox is mentioned, more

particularly, by Houzeau et Lancaster (“Bibliog. Générale,” Vol. II.

p. 167), also at pp. 12 and 220, Vol. II of Hutton’s abridgments of

the _Phil. Trans._; while full accounts of the many important

works of Borelli are to be found in “Biogr. Générale,” Vol. VI. pp.

700–701; Ninth “Britannica,” Vol. IV. p. 53; Larousse, “Dict. Univ.,”

Vol. II. p. 1003; “Chambers’ Encycl.,” 1888, Vol. II. p. 328; “La

Grande Encycl.,” Vol. VII. p. 405; Nicéron, “Mémoires,” Vol. VIII. p.

257; Vigneul-Marville, “Mélanges,” Vol. II. p. 122; Sachs, “Onomasticon

Literarium,” V. 40; Hagen, “Memoriæ Philosophorum,” Frankfort, 1710.

=A.D. 1613.=--Ridley (Marke), “Doctor in physicke and philosophie,

latly physition to the Emperour of Russia and one of ye eight

principals or elects of the College of Physitions in London,” is the

author of a small quarto entitled “A Short Treatise of Magnetical

Bodies and Motions,” published in London, 1613. Of this treatise,

Libri says that the author, in his preface, deals tolerantly with

the many and varied theories concerning magnetic bodies, instancing

many of the most notable from those of Pliny and Nicander to those of

Robert Norman. He is particularly emphatic concerning the production

of perpetual motion by means of the loadstone, finding it “by the

experience of many ingenious practices ... impossible to be done.”

From the notice given him in “Dict. of Nat. Biog.,” 1896, Vol.

XLVIII. pp. 285–286, we learn that in the above-named work, he claims

acquaintance with William Gilbert, whom he commends as the greatest

discoverer in magnetical science, and that after giving twenty-four

chapters on the properties and description of the magnet, he discusses

the variation of the compass and methods of estimating it in eight

chapters, the inclinatory needle in eight others, concluding with

a chapter on finding the longitude and one “of the matter of the

magnetical globe of the earth by the needle.”

In 1617, he published “Animadversions on a late work entitled

Magnetical Advertisement; or, Observations on the Nature and Properties

of the Loadstone.”

=References.=--A. Watt, “Bibliotheca Britannica,” Vol. II. p.

804, at p. 75_g_ Vol. I. of which (article, “Wm. Barlowe”) is

“A briefe discovery of the idle animadversions of Marke Ridley,

M.D.,” upon a treatise entitled “Magneticall Advertisements,”

London, 1618. Consult also “The Lancet” of August 7, 1897,

p. 349; Munk’s “College of Phys.,” Vol. I. p. 106; Ridlon’s

“Ancient Ryedales,” p. 425.

=A.D. 1616.=--Schouten (Guillaume Cornelissen--Willem Cornelisz),

Dutch navigator, indicates points lying in the midst of the Pacific and

south-east of the Marquesas Islands in which the variation is null.

Humboldt alludes to this (“Cosmos,” 1859, Vol. I. p. 182, and Vol.

V. p. 59) and says, “Even now there lies in this region a singular,

closed system of isogonic lines, in which every group of the internal

concentric curves indicates a smaller amount of variation.”

For Schouten, consult “Relation,” published by Aris Classen, Amst.,

1617; Larousse, “Dict. Univ.,” Vol. XIV. p. 375.

Under this same date, A.D. 1616, Chas. Pickering tells us that Wm.

Baffin (Churchill Coll. and Anders. II. 268) continued North to

“seventy-eight degrees,” as far as a Sound called by him “Thomas

Smith’s,” where the compass varied “fifty-six degrees to the westward,”

making the true North bear N.E. by E. The northern expanse of water

received the name of “Baffin’s Bay” (“Chron. Hist. of Plants,” Boston,

1879, p. 933).

=A.D. 1617.=--Strada (Famianus), an Italian author and Jesuit

priest, publishes his curious “Prolusiones Academicæ,” wherein he

describes (lib. ii. prol. 6) a contrivance consisting of two magnetic

needles attached to two dials each bearing a circle of letters so

arranged that when one needle is made to point to any letter on one

dial, the other needle points to the same letter upon the other dial.

The description is best given in his own words taken from the original

Latin (Stradæ, “Prol. Acad.,” Oxoniæ, 1662, “Magnes cur ferrum aut

aurum trahat,” pp. 326–335): “... If you wish your distant friend, to

whom no letter can come, to learn something, take a disc or dial, and

write round the edge of it the letters of the alphabet in the order

in which children learn them, and, in the centre, place horizontally

a rod, which has touched a magnet, so that it may move and indicate

whatever letter you wish. Then a similar dial being in the possession

of your friend, if you desire privately to speak to the friend whom

some share of the earth holds far from you, lay your hand on the globe,

and turn the movable iron as you see disposed along the margin of

all the letters which are required for the words. Hither and thither

turn the style and touch the letters, now this one, and now that....

Wonderful to relate, the far-distant friend sees the voluble iron

tremble without the touch of any person, and run now hither, now

thither; conscious he bends over it and marks the teaching of the rod.

When he sees the rod stand still, he, in his turn, if he thinks there

is anything to be answered, in like manner, by touching the various

letters, writes it back to his friend....”

REFERENCES.--“The Student; or, Oxford and Cambridge Misc.,”

1750, Vol. I. p. 354; Abbé Moigno’s “Traité de Tel. Elec.,” p.

58; Addison (Joseph), “Spectator” for December 6, 1711, No. 241

(p. 273, Vol. II. London ed., 1854); the “Guardian” for 1713,

No. 119, and “Nature,” Vol. XVI. pp. 268, 269. Also “Academy and

Literature” of January 7, 1905. Zachary Grey, in 1744 edition of

Butler’s “Hudibras,” quotes from the “Guardian.”

=A.D. 1620.=--Bacon (Sir Francis), by many considered the greatest

of English philosophers and philosophical writers (1561–1626), who

was knighted in 1603, became Earl of Verulam in 1618 and Viscount

St. Albans in 1620, produces the masterpiece of his genius, the

“Novum Organum,” after having twelve times copied and revised it. The

last-named work, observes Macaulay, “takes in at once all the domains

of science--all the past, the present and the future, all the errors

of two thousand years, all the encouraging signs of the passing times,

all the bright hopes of the coming age.” Prof. Playfair says of it

that “the power and compass of the mind which could form such a plan

beforehand, and trace not merely the outline but many of the most

minute ramifications of sciences which did not yet exist, must be an

object of admiration to all succeeding ages.”

It was Sir John Herschel who remarked that “previous to the publication

of the ‘Novum Organum’ natural philosophy, in any legitimate and

extensive sense of the word, could hardly be said to exist.” In the

address presented in 1623 by the University of Oxford to Sir Francis

Bacon, he is represented “as a mighty Hercules who had by his own hand

greatly advanced those pillars in the learned world which by the rest

of the world were supposed immovable.”

Treating of the electric fluid, Bacon has given (“Physiological

Remains,” London, 1648) a detailed list of attractive and

non-attractive bodies and the results of his very extensive experiments

and observations in physical science generally, as well as of the

investigations contained in Dr. Gilbert’s work. To the latter, however,

many allusions had already been made in Bacon’s “The Advancement

of Learning,” published during 1605, two years before he was made

Solicitor-General.

The most satisfactory analyzation of Bacon’s researches is to be found

in the attractive edition of his complete works published by Spedding,

Ellis and Heath, fifteen volumes, Boston, 1863. Therein will be seen

the following references to the magnet and magnetic virtue:

Vol. I. p. 435 (note). In Gilbert’s philosophy, the earth’s

magnetic action is not distinguished from gravity (De Mundo, II.

c. 3). That the magnetic action of the earth or of a magnet is

confined to a definite orb, appears from a variety of passages

(see “De Magnete,” II. c. 7, and the definitions prefixed to

this work). Gilbert distinguished between the “Orb of Virtue”

which includes the whole space through which any magnetic action

extends, and the “Orb of Coition” which is _totum illud

spatium per quod minimum magneticum per magnetem movetur_. He

asserts that the orb of the magnetic virtue extends to the moon

and ascribes the moon’s inequalities to the effects it produces

(“De Mundo,” II. c. 19).

Vol. VIII. Aphorisms. “If, before the discovery of the magnet,

any one had said that a certain instrument had been invented

by means of which the quarters and points of the heavens could

be taken and distinguished with exactness ... it would have

been judged altogether incredible ...” (pp. 141–142). “The

‘Clandestine Instances’--which I also call ‘Instances of the

Twilight’ [the attraction or coming together of bodies]--and

which are pretty nearly the opposite of ‘Striking Instances....’

The most remarkable ‘Striking Instance’ is the magnet ... a

‘Clandestine Instance’ is a magnet armed with iron; or, rather,

the iron is an armed magnet ...” (pp. 224–226). “The polarity

of the iron needle when touched with the magnet” (p. 261).

“The magnetic or attractive virtue admits of media without

distinction, nor is the virtue impeded in any kind of a medium”

(p. 269). “There is no medium known by the interposition of

which the operation of the magnet, in drawing iron, is entirely

prevented” (pp. 285–286). “A piece of a magnet does not draw

so much iron as the whole magnet” (p. 301). “As for the help

derived from the virtue of a cognate body, it is well seen in

an armed magnet, which excites in iron the virtue of detaining

iron by similarity of substance; the torpor of the iron being

cast off by the virtue of the magnet” (p. 311). “There are

four virtues or operations in the magnet ... the first is the

attraction of magnet to magnet, or of iron to magnet, or of

magnetised iron to iron; the second is its polarity, and at the

same time its declination; the third, its power of penetrating

through gold, glass, stone, everything; the fourth, its power

of communicating its virtue from stone to iron, and from iron

to iron, without communication of substance” (p. 313). “But the

flight of iron from one pole of the magnet is well observed by

Gilbert to be not a flight strictly speaking, but a conformity

and meeting in a more convenient situation” (p. 315). “The

magnet endues iron with a new disposition of its parts and a

conformable motion, but loses nothing of its own virtue” (p.

318).

Vol. IX. In the fifth book of “De Augmentis Scientiarum,” these

questions are asked: (1) A magnet attracts a solid piece of

iron; will a piece of a magnet dipped in a dissolution of iron

attract the iron itself and so get a coating of iron? (2) Again,

the magnetic needle turns to the pole; does it, in so doing,

follow the same course as the heavenly bodies? (3) And, if one

should turn the needle the wrong way, that is, point it to the

South and hold it there for a while, and then let it go; would

it, in returning to the North, go round by the West rather than

by the East? (pp. 75–76).

Vol. X. This contains, at pp. 269–272, the “Inquiry respecting

the Magnet,” of which the original paper is to be found in Vol.

IV. pp. 121–125. In Dr. Rawley’s list of works composed by

Bacon, during the last five years of his life, this “Inquisitio

de Magnete,” first published in 1658, stands last but two. At

p. 335 this same Vol. X will be found an extract from “De fluxu

et reflexu maris” (“The ebb and flow of the sea”) relative to

the inquiry as to whether the earth itself is a magnet, as was

asserted by Gilbert.

Besides the “Clandestine Instances” or “Instances of the Twilight”

alluded to above, mention could have been made more particularly of

Bacon’s observations (in s. 3 of the “Nov. Organ.”) under the direct

headings of “Instantiæ Citantes ... Supplementi ... Radii ... Magicæ,”

as well as of “Motus Magneticus ... Excitationis ... Fugæ,” etc., which

are fully explained at ss. 190–200 of Sir John Herschel’s “Discourse on

the study of Natural Philosophy.”

They have been analyzed as follows:

_Instantiæ Citantes_, to which may be reduced the “discovery of

a moving magnetic fluid, or an action circular and perpendicular

to the electrical current, yet connected with it.”

_Instantiæ Supplementi_, such as the magnet which attracts iron

through many substances that may be interposed. Perhaps, says

he, “some medium may be found to deaden this virtue more than

any other medium; such an instance of _substitution_, would be

in the way of degree, or _approximation_”; that is, it would

approach toward destroying the magnetic virtue. Iron possesses,

perhaps, this quality in a more marked manner than any other

substance.

_Instantiæ Radii_, leading to the suggestion that there may

exist some kind of “magnetic virtue which operates by consent,

between the globe of the earth and heavenly bodies; or between

the globe of the moon and the waters of the sea; or between the

starry heavens and the planets, by which they may be drawn to

their apogees,” or greatest distances from the earth.

_Instantiæ Magicæ_, such as the loadstone animating a number of

needles without loss of its own magnetism.

_Motus Magneticus_, such as the attraction of the heavenly

bodies, from an idea, perhaps, that it might be due to a species

of magnetism.

_Motus Excitationis_, such as the new property which is given to

iron by the magnet without any loss of power by the latter.

_Motus Fugæ_, such as “the repulsion of electrified pith balls;

also of the similar poles of two magnets. In the latter case,

all the force of a strong man has proved insufficient to make

the two north poles touch each other.”

The last-named work of Sir John Herschel is alluded to, under the

heading of “Prerogative Instances” (“Prærogativæ Instantiarum”)

by Thomas Fowler, who calls attention to the fact that among the

contemporaries of Francis Bacon by whom the Copernican theory was

rejected are: Tycho Brahé (who, however--having died in 1601--did not

live to become acquainted with the discoveries of Galileo); Vieta, the

greatest mathematician of the sixteenth century (who died as early as

1603); Christopher Clavius (who was employed by Gregory XIII to reform

the Calendar and was called the Euclid of his age); and possibly, from

his silence, the famous mechanician Stevinus (Delambre, “Histoire de

l’Astronomie Moderne”).

REFERENCES.--The works of Sir Francis Bacon, Lord Chancellor

of England, by Basil Montagu, 16 vols., London, 1825–1834,

and the review thereof made by Thomas Babington Macaulay

(“Essays,” 1855, Vol. II. pp. 142–254 (“Edinburgh Review,” July

1837); Dr. W. Windelbrand, “History of Philosophy,” New York,

1893, translated by Jas. H. Tufts, pp. 380–388; Dr. Friedrich

Ueberweg, “History of Philosophy,” translated by Geo. S.

Morris, New York, 1885, Vol. II. pp. 33–38; Leopold Von Ranke,

“History of England,” Vol. I. pp. 455–459, Vol. III. p. 383;

William Whewell, “The Philosophy of the Inductive Sciences,”

London 1840, Vol. II. pp. 388–413; “Critical Dictionary of

English Literature,” S. Austin Allibone, Philad. 1888, Vol.

I. pp. 89–96; “Catalogue Général des livres imprimés de la

Bibliot. Nation.,” Paris, 1901, Vol. VI. pp. 236–253; Chas.

Wells Moulton, “Library of Literary Criticism,” Vol. I. pp.

638–669; “The Philosophical Works of Francis Bacon,” by John

M. Robertson, New York, 1905; “The Grammar of Science,” by

Karl Pearson, London, 1900, pp. 506–508; “Encycl. Britann.,”

Edinburgh, 1842, seventh edition, Vol. I. as per Index pages

16–17 and at “Dissertation First,” pp. 32–40; “Essai Theorique

... des connaissances humaines,” par G. Tiberghien, Bruxelles,

1844, Vol. II. pp. 409–419; Geo Miller, “History Philosophically

Illustrated,” London, 1849, Vol. II. p. 430; “Francis Bacon,”

by B. G. Lovejoy, London, 1888; “His Life and Character,” pp.

1–188, and “His Essays and Extracts,” pp. 19–277; “Francis

Bacon,” by Kuno Fisher, London, 1857; “Encycl. Brit.” ninth

edition, Vol. III. pp. 200–218; Bacon’s “Novum Organum,” by

Thomas Fowler, New York, 1881, and Oxford, 1889; “Histoire des

Sciences,” par F. L. M. Maupied, Paris, 1847, Vol. II. pp.

252–281, for “Enumeration Méthodique--Eléments--Analyse--des

ouvrages de Francis Bacon”; “Library of Useful Knowledge,” for

account of Lord Bacon’s “Novum Organum”; “Epitome of Electricity

and Galvanism,” Philad., 1809, pp. xvi, 105; Whewell, “History

of the Inductive Sciences,” Vol. I. pp. 339, 385, 494, 530; Van

Swinden, “Recueil de Mémoires ...” La Haye, 1784, Vol. II. pp.

355, 364, 369–370; and, for an exhaustive biographical account

of Francis Bacon, consult the “English Cyclopædia,” Vol. I.

pp. 470–476. It is stated by C. R. Weld in his “History,” Vol.

I. p. 64, that the establishment of the Royal Society was much

accelerated by the writings of Lord Bacon (Buchmeri, “Acad. Nat.

curi. Hist.”).

=A.D. 1620–1655.=--Bergerac (Savinien Cyrano de), a very witty French

writer, is the author of a fragment on physics, as well as of a curious

philosophical romance, “Histoire comique des états et empires de la

lune,” a translation from which latter is here given, as in a measure

suggesting the phonograph: “On opening the box, I found a number of

metallic springs and a quantity of machinery resembling the interior

of our clocks. It was, in truth, to me a book, indeed, a miraculous

book, for it had neither leaves nor characters, and to read it, one

had no need of eyes, the ears alone answering the purpose. It was only

necessary to start the little machine, whence would soon come all the

distinct and different sounds common to the human voice.”

Another translation reads as follows: “On opening the box I found

inside a concern of metal, something like one of our watches, full of

curious little springs and minute machinery. It was really a book,

but a wonderful book that has no leaves or letters; a book, for the

understanding of which the eyes are of no use--only the ears are

necessary. When any one wishes to read, he winds up the machine with

its great number of nerves of all kinds, and turns the pointer to the

chapter he wishes to hear, when there come out, as if from the mouth

of a man or of an instrument of music, the distinct and various sounds

which serve the Great Lunarians as the expression of language.”

As has been said by one of his biographers, “amid the extravagance

of some of his works, Bergerac nevertheless exhibited a pretty good

acquaintance with the philosophy of Descartes.”

REFERENCES.--Article “Aeronautics” in the “Encycl. Brit.,” 1853,

Vol. II. p. 168; Larousse, “Dict.,” Vol. V. p. 730.

=A.D. 1621.=--Helmont (Jean Baptiste van), famous Belgian scientist,

publishes in Paris his “De Magnetica,” etc. (on the magnetic cure

of wounds). His theories on magnetism greatly resemble those of

Paracelsus, but in his treatment of them he shows himself much

superior to the Swiss alchemist, whom Dr. Hœfer says he took as his

model. “Magnetism,” Van Helmont observes, “is an unknown property of

a heavenly nature, very much resembling the stars, and not at all

impeded by any boundaries of space or time.... Every created being

possesses his own celestial power and is closely allied with heaven

... the spirit is everywhere diffused; and the spirit is the medium of

magnetism ... it is not the spirits of heaven and of hell which are

masters over physical nature, but the soul and spirit of man which are

concealed in him as the fire is concealed in the flint.”

The above-named work of Van Helmont was “translated, illustrated and

ampliated,” in 1650 by Dr. Walter Charleton, physician in ordinary to

King Charles I, under the name of “A Ternary of Paradoxes.” From its

interesting contents, we make the following extracts:

_Page 10._ “A loadstone placed upon a small trencher of wood,

floating on water, does instantly in one determinate point

_australize_, and in the other _septentrionate_ ... all which

various and admirable effects of the loadstone, thou maiest,

if thy judgement relish them, finde made good by multiplyed

observations, by William Gilbert, not many yeers past, a

physician in London, in his book, ‘De Magnete’: of which subject

no man ever writ more judiciously or experimentally: and by

whose industry the variation of the compasse may be restored....”

_Page 12._ “There is a book imprinted at Franekera, in the year

1611, by Vldericus Dominicus Balck, of the _Lamp of Life_. In

which you shall finde, out of Paracelsus, the true magneticall

cure of most diseases, as of the Dropsie, Gout, Jaundice, etc.”

_Page 15._ “Doth not the needle of the Mariner’s Compasse,

through a firme glasse, closely sealed up with melted soder (in

which there can be no pore or crany discovered) steer it self to

the Artick pole? ... wherefore the same numericall _accident_

streaming in one continued _radius_ from the loadstone into the

_aer_, passes through the glasse, and perhaps goes as farre as

to touch the pole it self....”

_Page 38._ “Wherefore the loadstone owes its polarity to a

natural inhærent faculty, flowing from its owne seminall

entity, and not to any forreigne alliciency, or attractive

influx transmitted from the north star. But that otherwise the

loadstone may, by its own instinct, be elevated towards the

Zenith, we have upon ocular demonstration found it true, by a

certain instrument invented by Guilielme Guilbert (the glory

of which excellent invention Ludovicus Fonseca hath lately

endeavoured to ravish) ... which by the spontaneous elevation of

the loadstone in a brasse ring suspended by a thread or small

wier, shews not only the latitude but also the altitude of the

pole, in all places of the earth.”

Page 39. “... the loadstone is endued with a _domestick pilot, a

directive faculty_, which guides it to some determinate place,

but is not at all attracted by the pole.”

Page 40. “The loadstone onely by the affriction of _Garlick_,

amits its _verticity_, and neglects the pole, conserving to

it self, in the meane time, its peculiar forme, materiall

constitution, and all other dependent proprieties. The reason,

because _Garlick_ is the loadstone’s proper Opium, and by it

that spirituall sensation in the magnet is consopited and layd

asleep.... Verily, that alliciency of the pole must be extreame

weake and of inconsiderable energy, which passing through so

many and so immense orbes of heaven, and striking through great

and firme buildings, and thick walls, cannot yet be of power

sufficient to pierce the thin juice of Garlick or the fume of

Mercury....”

Page 42. “There is therefore inhærent in the magnet an

_influentiall virtue_, which, being not obliged to the

propinquinty or comtiguous admotion of its object, is after

the nobler names of coelestiall influences, freely and without

interruption or languor transmitted so farre as to the pole it

self: since there is a spontaneous _eradiation_, or emission of

atomicall _radii_ from the body of the magnet to the pole.”

Page 74. “That the magnetisme of the loadstone and other

inanimate creatures is performed by a certaine naturall

sensation, the immediate anthrix of all sympathy, is a truth

unquestionable.”

Page 75. “For by one phansy it is directed to iron, and by

another to the pole ... the phansy of _amber_ delights to allect

strawes, chaffe, and other festucous bodies; by an attraction,

we confesse, observe obscure and weake enough, yet sufficiently

manifest and strong to attest an _Electricity_ or attractive

signature....”

REFERENCES.--“Dict. of Nat. Biog.,” Vol. X. pp. 116–119,

containing a full list of Charleton’s works; Thomson, “Hist. of

the Roy. Soc.,” 1812, p. 3; Munk, “Coll. of Phys.,” 1878, Vol.

I. p. 390; “Journal des Savants” for February and March 1850,

June 1851; Mme. Blavatsky, “Isis Unveiled,” Vol. I. p. 170;

Eloy, “Dict. Hist. de la Médecine,” Vol. II. pp. 478–482; “Dict.

Hist. de la Médecine,” par. J. E. Dezeimers, Paris, 1839, Vol.

III. pp. 97–104; “Ency. Brit.,” ninth edition, Vol. XI. p. 638;

“History and Heroes of the Art of Medicine,” by J. Rutherfurd

Russell, London, 1861, pp. 197–204; Larousse, “Dict. Univ.,”

Vol. IX. p. 158; Van Swinden, “Recueil,” La Haye, 1784, Vol.

II. pp. 351–352, 361–363; Joseph Ennemoser, “The History of

Magic,” London, 1854, Vol. II. pp. 242–253.

=A.D. 1623.=--Hervart--Heroart--Herwart--Hörwarth (Joannes Fridericus),

son of Johann Georg Hervart ab Hohenburg, the well-known scientist

(1554–1622), who during forty-five years occupied the post of Bavarian

Chancellor under three reigning princes--completes his father’s work

entitled “_Admiranda ethnicæ theologiæ ..._” which, Larousse says

(“Dictionnaire Universel,” Vol. IX. p. 250), was published at Munich,

1624, and in which he demonstrates that the earlier Egyptian divinities

were natural phenomena personified and adored under symbolic names.

Michaud, who reiterates this (“Biographie Universelle,” Vol. XIX.

p. 364), speaks of the edition which appeared at Munich in 1626,

and he also states that, at the end of the latter, will be found

“_Exacta temporum ... chronologiæ vulgaris errores_,” which is the

continuation of the “_Chronologia Nova_,” left unfinished by the

Bavarian Chancellor. This is, in fact, so mentioned in the only copy

possessed by the British Museum, which was published by J. F. Hervart

ab Hohenburg at Ingolstadii, 1623, and of which the title reads:

“_Admiranda Ethnicæ Theologiæ Mysteria propalata. Ubi lapidem magnetem

antiquissimis passim nationibus pro Deo-deocultum: et artem qua

navigationes magneticæ per universum orbem instituerentur...._”

Libri’s “Catalogue,” 1861, Part I. p. 405, No. 3703, has the following

entry: “_Admiranda Ethnicæ ... ubi Lapidem Magnetem antiquissimis

Nationibus pro Deo cultum commonstratur_ ...” Ingolstadii, 1623. The

work itself endeavours to prove that the loadstone’s properties were

well known to the ancients.

The “General Biographical Dictionary” of Alexander Chalmers, London,

1814, Vol. XVII. p. 426, makes following entry: “Herwart (or Hervart)

John George, Chancellor of Bavaria at the beginning of the seventeenth

century, published some works wherein his learning was more displayed

than his judgment, in supporting the most extravagant systems. Two

of his works are: ‘_Chronologia nova et vera_,’ in two parts, 1622

and 1626, and ‘_Admiranda Ethnicæ Theologicæ Mysteria propalata, de

antiquissima veterum nationum superstitione, qua lapis Magnes pro Deo

habitus colebatur_,’ Monach, 1626, quarto. It was here asserted that

the ancient Egyptians worshipped the magnet,” etc. (see Deveria, under

B.C. 321).

REFERENCES.--Allusions to Hervart, made at p. 546, Vol. XXIV.

of Dr. Hœfer’s 1861 “Nouvelle Biographie Générale,” or at p.

546, Vol. XXVIII of the 1858 edition, and also at p. 163, Vol.

II of the “Bibliographie Générale de l’Astronomie,” by Houzeau

et Lancaster, Bruxelles, 1882. Likewise Chr. G. Jöcher,

“Compendiöses Gelehrten Lexicon,” Leipzig, 1787, Vol. II. p.

1969, and “A New General Biogr. Dict.,” London, 1850, Vol. VIII.

p. 304.

=A.D. 1624.=--Gunter (Edmund), professor of astronomy at Gresham

College, publishes his work “Of the Sector, Cross-Staff, and other

Instruments,” at Chap. V of the second book of which he gives the

result of the eight observations he made on the variation of the

variation “in various parts of the ground” at Limehouse on the 13th

of June, 1622. His observations of the declination, as given by Prof.

Gellibrand, are detailed at Chap. I of Walker’s “Ter. and Cos. Mag.,”

Cambridge, 1866.

REFERENCES.--De La Rive, “Electricity,” etc., Vol. I. p. 165;

Poggendorff, “Geschichte der Physik,” Leipzig, 1879, p. 275.

=A.D. 1625.=--Carpenter (Nathaniel), Dean of Ireland, well-known

mathematician, publishes at Oxford, “Geography delineated forth in

two bookes, containing the sphæricall and topicall parts thereof,”

wherein he thus alludes to Dr. Gilbert’s “De Magnete”: “Magneticall

proprieties, I find in ancient writers, as little knowne as their

causes; and if any matter herein were broached, it was merely

conjectural, and depending on no certain demonstration; neither had we

any certain or satisfactory knowledge of the thing vntill such time as

it pleased God to raise vp one of our countrymen, D. Gilbert, who, to

his euerlasting praise, hath trodden out a new path to Philosophie, and

on the Loadstone, erected a large Trophie to commend him to posterity.

This famous Doctor being as pregnant in witty apprehension as diligent

in curious search of naturall causes, after many experiments and long

enquiry, found the causes of most magneticall motions and proprieties

hid in the magneticall _temper_ and constitution of the Earth,

and that the earth it selfe was a meere magneticall body challenging

all those proprieties, and more than haue expressed themselves in

the Loadstone; which opinion of his was no sooner broached than it

was embraced, and wel-commed by many prime wits as well English as

Forraine. Insomuch that it hath of late taken large root and gotten

much ground of our vulgar Philosophie.”

REFERENCES.--“Nature,” September 26, 1901; “Dict. of Nat.

Biogr.,” Vol. IX. pp. 161–162; Larousse, “Dict.,” Vol. IV. p.

438; Prince’s “Worthies” (1810), pp. 173–175, 603.

=A.D. 1625.=--Naudé (Gabriel), a celebrated French savant and one

of the most learned of his day, also physician to King Louis XIII, and

an intimate friend of Gassendi, is the author of “Apologie pour tous,”

etc. (“Apology for great men falsely accused of magic”), of which other

editions appeared in 1652, 1669 and 1712. The magico-theosophical

philosophy, as Madame Blavatsky expresses it, is fully indicated in

his work, and he proved to be the warmest defender of the doctrines of

occult magnetism, of which he was one of the first propounders.

REFERENCES.--“Biog. Générale,” Vol. XXXVII. pp. 514–518;

P. Hallé, “Gab. Naudé Elogium”; N. Sanson, “Hist. Chr.

d’Abbeville,” 1653; Sainte Beuve, “Portraits Littéraires,” 1855;

Alf. Franklin, “Hist. de la Biblioth. Mazarine,” 1860.

=A.D. 1627.=--Hakewill (George), Archdeacon of Surrey, publishes

at Oxford, England, the first edition of “An Apologie or Declaration of

the Power and Providence of God,” the tenth chapter, fourth section of

the third book of which alludes to the use of the “mariner’s compass

or sea-card, as also of another excellent invention sayd to be lately

found out upon the loadstone.” As the reviewer justly observes: “While

perusing his description one can hardly imagine that the writer had not

in his mind’s eye one of our modern telegraphic instruments ... and

it will be seen that the date at which his work is written was nearly

two hundred years prior to the first attempt made to communicate at a

distance by means of magnetic needles.”

Hakewill alludes (“Apologie,” 1635, lib. ii. p. 97) to

Hipparchus--Abraxis--“who reports that, in his time, the starre

commonly called the Polar Starre, which is in the tayle of the lesser

Beare, was twelve degrees and two-fifths distant from the Pole of the

Æquator. This starre, from age to age, hath insensibly still crept

nearer to the pole so that at this present it is not past three degrees

distant from the pole of the Æquator. When this starre then shall come

to touch the Pole, there being no farther place left for it to go

forward (which may well enough come to pass with five or six hundred

yeares) it is likely that then there shall be a great change of things,

and that this time is the period which God hath prefixed to Nature”

(see Morell’s “Elem. ... Phil. and Sc.,” London, 1827, pp. 116–119

_et seq._).

Mention of the star in the tail of Ursa Major is made by Gilbert, (“De

Magnete”),[41] in connection (1) with Marcilius Ficinus, who, says he,

seeks in that constellation the cause of the magnetic direction, as he

believes that in the loadstone the potency of Ursa prevails and hence

is transferred to the iron; (2) with Cardan, who assigns the cause of

variation to its rising, for he thinks variation is always to be relied

upon at the rising of the star; (3) with Lucas Gauricus, who holds that

the loadstone beneath the tail of Ursa Major is ruled by the planets

Saturn and Mars; (4) with Gaudentius Merula, who believes that the

loadstone draws iron and makes it point North because it is of a higher

order than is the iron in the Bear.

REFERENCES.--Larousse, “Dict. Univ.,” Vol. IX. p. 26;

“Dict. of Nat. Biog.,” Vol. XXIV. pp. 6–8; Walton and Cotton,

“Complete Angler,” New York and London, 1847, Part I. p. 118.

=A.D. 1628.=--Leurechon (Jean), a student belonging to the Order

of Jesuits (1591–1670), who became the confessor of Charles IV of

Lorraine, publishes, under the name H. Van Etten, “La Récréation

Mathématique,” carefully revised editions of which were made by Claude

Mydorge and Denis Henrion in 1630, 1638 and 1661. In these, Leurechon

alludes to the reported transmission of intelligence by the agency of

a magnet or other like stone, saying: “The invention is beautiful, but

I do not think there can be found in the world a magnet that has such

virtue.”

REFERENCES.--Georges Maupin, “Opinions touchant la

mathématique,” Paris, 1898, pp. 20–24; Larousse, “Dict.,” Vol.

X. p. 436; “Sc. Am. Suppl.,” Nos. 56, p. 881, and 384, p. 6125.

The curious title-page of the English version of Leurechon’s work,

published by T. Cotes in 1633, merits reproduction: “Mathematicall

Recreations, or a Collection of sundrie Problemes, extracted out of the

Ancient and Moderne Philosophers, as secrets in nature, and experiments

in Arithmeticke, Geometrie, Cosmographie, Horologographie, Astronomie,

Navigation, Musicke, Optickes, Chimestrie, Waterworkes, Fireworks,

etc., Fit for Schollers, Students, and Gentlemen ... lately compiled in

French by Henry Van Hetten. And now delivered in the English tongue.”

Claude Mydorge, as stated in the “Biog. Gén.,” Vol. XXXVII. p. 87, was

a French scientist (1585–1647), a very close friend of Descartes, and,

according to Baillet, was next to Vieta, the foremost mathematician of

his day. The second edition of his “Examen du livre des Récréations

Mathématiques (du Père Leurechon),” contains notes of Denis Henrion

following the observations of Père Mersenne in “Universæ ...” Paris,

1639 (see Bouillet, “Vie de Descartes,” Vol. I. pp. 36–37, 149–150, and

Vol. II. pp. 43, 76, 78, 325).

Denis Henrion was also a French mathematician, who died about 1640. He

was the author of many very meritorious papers, notably of a “Traité

des Globes et de leurs usages,” 1618, translated from the Latin of

Robert Hues, 1593, 1594 (Larousse, “Dict. Univ.,” Vol. IX. p. 192).

=A.D. 1629.=--Cabæus--Cabeo (Nicolaus), a learned Jesuit of Ferrara,

describes (“Philosophia Magnetica”)[42] numerous experiments made

by him to ascertain the possibility of two persons communicating

intelligence by means of magnetized needles.

Cabæus was the first to observe electrical repulsion, and he thus

announces his discovery in the tenth chapter of the above-named work:

“Magnetic attractions and repulsions are physical actions which

take place through the instrumentality of a certain quality of the

intermediate space, said quality extending from the influencing to the

influenced body.... Bodies are not moved by sympathy or antipathy,

unless it be by means of certain forces which are uniformly diffused.

When these forces reach a body that is suitable they produce changes

in it, but they do not sensibly affect the intermediate space nor the

non-kindred bodies close by it....”

The “Philosophia Magnetica” is the second Latin book published on

electricity, Gilbert’s “De Magnete” being the first.

REFERENCES.--Becquerel, “Résumé,” Chap. III; Stuello, “Bibl.

Scrip. S. J.,” Rome, 1676; Francisco de Lanis, “Magist. nat. et

artis,” 1684; L. L. de Vallemont, “Description de l’aimant,”

1692, pp. 167, 170; Dechales C. F. Milliet, “Cursus seu Mundus

Mathem.,” 1674, 1690.

=A.D. 1632.=--Sarpi (Pietro)--Fra Paolo Sarpi--Father Paul--Paulus

Venetus--Paolo Sarpi Veneto (_b._ 1552, _d._ 1623), who was the author

of the celebrated history of the Council of Trent (“the rarest piece of

history the world ever saw”) is referred to by Gilbert in “De Magnete,”

Book I. chap. i. Therein, he says that Baptista Porta, who has made the

seventh book of his “Magia Naturalis” a very storehouse and repertory

of magnetic wonders, knows little about the movements of the loadstone

and never has seen much of them, and that a great deal of what he has

learned about its obvious properties, either through Messer Paolo, the

Venetian, or through his own studies, is not very accurately noted and

observed.

In the introduction to the 1658 edition of his “Natural Magick,” Porta

admits that he gained some knowledge of Sarpi, who, says he, is of all

men he ever knew the most learned and skilful and the ornament and

splendour not only of Venice or of Italy, but of the entire world.

Bertelli refers (“Memor. sopra P. Peregrino,” p. 24, note) to P.

Garbio’s “Annali di Serviti,” Lucca, 1721, Vol. II. pp. 263, 272, 274,

and to Fra Fulgenzio Micanzio’s “Life of Sarpi,” Helmstat--Verona,

1750, in which it is stated that not only Porta but likewise a

celebrated _ultramontane_ studied magnetism under him. Garbio asks:

“Could this _ultramontane_ be Gilbert of Colchester?”

By Griselini (“Vita de Fra P. Sarpi”--memoria anecdote--Lausanne,

1760), Paolo is said to have written a treatise on the magnet and to

have therein recorded many observations, including the earliest mention

that magnetic properties are destroyed by fire.

Bertelli--whose afore-named memoir we must confine ourselves to, as

it is more satisfactory than are the accounts elsewhere given--makes

mention that he has had in his possession, by courtesy of Sig. Giuseppe

Valentinelli, the Royal Librarian of the Marciana at Venice, copy of

a manuscript (Cod. CXXIX, classe 2, MS. Ital.) containing a brief

comparison of Sarpi’s magnetic researches with those of Musschenbroek.

This manuscript is again alluded to by Bertelli (Memor., p. 88)

wherein it is said that lines 5–38 of the first column, p. 170, are

headed “Observations of F.P.S. on the loadstone, collated with P.

Musschenbroek’s Researches,” and embrace five paragraphs translated as

follows:

1. The author had first tried the action of one magnet on

another without entering into the question of calculation,

but modern authors have, in view of the observations made,

endeavoured to discover a method of computing magnetic forces

in any proportion to the distances, and in the same better

regulated systems they have discovered the cause to be uncertain

(or varying) owing to the contemporaneous action of magnetic

repulsion.

2. He was acquainted with the well-known action of the

magnet on iron, but he understood--as even at this day

some understand--that it was caused by the atmosphere. New

experiments have made us seriously doubt this. He did not pay

attention to the proportion of the magnetic forces as compared

with the distances of iron, to the discovery of which the

efforts of present philosophers are directed but in vain. He

saw, however, that the facility or difficulty of attraction

depends upon the size of the iron (maximum and minimum).

3. He was not ignorant of the direction of the magnet and of

iron rubbed with the magnet towards certain quarters of the sky

when he mentions the new discovery of the poles in the magnet,

and the variation of the magnetized needle, from the Northern or

the Southern quarters, but he did not know a greater number than

two poles found in the magnet, the variation of the declination,

or, I should rather say, the uncertainty of the variation and

the different inclinations of the needle at different places on

the earth.

4. Almost all the experiments referred to by Academies, with

reference to the action of one piece of iron on another piece

of iron, magnetized and not magnetized, and with regard to the

changes of forces which arise from the various inflections of

iron, have been sufficiently sketched out by F. P. S.

5. The magnetic effects acquired by an old piece of iron

continually exposed to the air have also been alluded to. Now,

however, natural philosophers have observed that this iron

exposed for a length of time in the magnetic meridian points

with greater readiness to the above-mentioned quarters. They

have, moreover, ascertained that iron when heated and afterwards

cooled in water is more sensitive to magnetization: which is

directly opposed to the opinion of F. P. S.

Bertelli further remarks that, from information given in the

manuscript, it is seen that Sarpi was at that time acquainted with the

greater number of the magnetic phenomena referred to by Porta, and

developed by Gilbert, viz.:

1. The reciprocal action of magnets;

2. The action of magnets on iron;

3. The manifestation of magnetic activity about the poles

(sphere of action or field of force);

4. The _Maximum_ and the _Minimum_ of the attractive

force of magnets on iron, according to the size of the latter;

5. The inversion of polarity which may arise in the

magnetization of needles--(but not the corresponding

poles--the magnetic variation or declination--Petrus

Peregrinus, A.D. 1269--yet not the variation of the

variation--Henry Gellibrand, A.D. 1635--nor the dip or

inclination--Robert Norman, A.D. 1576).

6. The magnetic properties acquired by iron constantly exposed

to the air.

After detailing the observations of Giulio Cesare Moderati, Filippo

Costa (Costæus) of Mantua, Ulysses Aldrovandi, Francesco Acoromboni,

Luigi Matteini, Father Garzoni and Father Cabæus concerning the

magnetized ironwork of the belfry of the church of St. Augustine at

Arimini (the parochial church of St. John the Baptist, which at that

time, 1586, belonged to the monks of St. Augustine) and relative to the

iron rail in the belfry of the tower of St. Laurence at Rome, Bertelli

says: “From all that precedes, we gather at all events, that the fact

of the spontaneous magnetization of iron was well known in Italy before

Sarpi, Porta and Gilbert. This, Gilbert, and still better Cabæus,

explained as the influence of terrestrial magnetism. However, with

regard to the observations of the needle’s deviation made by Father

Garzoni at Rome, we can, without having attributed it, as does Cabæus,

to the magnetization of pieces of iron concealed in its wall, explain

it, as is done in the new and important experiments of the illustrious

professor Silvestro Gherardi, who attributes it to the magnetic

polarity of the _Mattoni_ [bricks] in the structure itself.”

It is said by Humboldt (“Cosmos,” 1849, Vol. II. p. 718, note) that

this observation, the first of the kind, was made on the tower of

the church of the Augustines at Mantua (Mantova) and that Grimaldi

and Gassendi were acquainted with similar instances (instancing the

cross of the church of St. Jean, at Aix, in Provence), in geographical

latitudes where the inclination of the magnetic needle is very

considerable. Some writers give Gassendi’s observation as occurring

during 1632 (see Rohaulti, “Physica,” 1718, Par. III. cap. 8, p. 399;

or, Rohault’s “System of Nat. Phil.,” 1728, p. 176).

“As the iron cross of an hundred weight upon the Church of St. John

in Ariminum, or that load-stoned iron of Cæsar Moderatus, set down by

Aldrovandus” (Sir Thomas Browne, “Pseudodoxia Epidemica,” 1658, p. 66).

Consult “Lettera dell’Eccel. Cavallara.,” Mantova, 1586, for a detailed

account of this discovery, made January 6, of the last-named year. The

iron rod supported a brick ornament in the form of an acorn, and stood

on a pyramid at the summit of the belfry of the church of St. Augustine

(Cabæus, “Philos. Magn.,” p. 62; “Ulysses Aldrovandi, Patr. Bonon ...

Barthol. Ambros ...” Lib. i, cap. 6, p. 134).

For the account given by Aldrovandi of the Arimini observation and for

references to Browne’s “Pseudodoxia Epidemica,” as well as to Boyle’s

“Experiments,” see p. 53 of the valuable “Notes on the ‘De Magnete’ of

Dr. William Gilbert,” by Silvanus P. Thompson, attached to the English

translation of the original 1600 edition, which was so attractively

produced by the Gilbert Club during the year 1900. Dr. Thompson further

gives, at the page following (54), additional references to examples of

iron acquiring strong permanent magnetism from the earth.

REFERENCES.--Biography of Sarpi in the “Encycl. Brit.,” ninth

edition, Vol. XXI. pp. 311–313; F. Micanzio, “Vita de F.

P. Sarpi,” Verona, 1750; Rev. Alex. Robertson, “Fra Paolo

Sarpi--the greatest of the Venetians,” 1894; Hallam, “Intro.

to Lit.,” 1839, Vol. II. p. 464; U. Aldrovandi, “Musæum

Metallicum,” 1648, p. 134; Tiraboschi, “Storia della Lettera,”

Modena, 1794, Vol. VI. part ii. p. 506; Sarpi’s Complete Works,

first published at Helmstat, 1750; Fabroni, “Vitæ Italorum,”

Pisa, 1798; Giovini, “Vita,” Brussels, 1836; “Engl. Cycl.,”

Biography, Vol. IV. pp. 695–697; Larousse, “Dict. Univ.” Vol.

XIV. pp. 230–231; “History of the reign of Charles the Fifth,”

by Wm. Robertson and Wm. H. Prescott, Philadelphia, 1883, Vol.

III. p. 68; “Dict. Hist. de la Médecine,” N. F. J. Eloy, Mons,

1778, Vol. IV. pp. 180–181; “The Atlantic Monthly,” New York,

January and February, 1904, wherein the author, Andrew D. White,

ranks Sarpi with Machiavelli and Galileo; Libri, “Hist. des Sc.

Mathém.” Paris, 1838, Vol. IV. p. 214, note.

=A.D. 1632.=--Gassendi (Pierre), an eminent French savant, professor at

the Royal College of France, “ranked by Barrow among the most eminent

mathematicians of the age, and mentioned with Galileo, Gilbert and

Descartes,” discovers that a part of the iron cross of the Church of

St. Jean at Aix possesses all the properties of a loadstone after being

struck by lightning and lying in one position a certain length of time.

Gilbert mentions, “De Magnete,” 1600, Book III. chap. xii.) that the

fact of magnetism being imparted to an iron bar by the earth was first

ascertained by examining the rod upon the tower of the church of St.

Augustine at Arimini (Sir Thomas Browne, “Pseud. Epidemica,” London,

1650, p. 48; U. Aldrovandi, “Musæum Metallicum,” Milan, 1648, p. 134).

In the “Vie de Pierre Gassendi,” par le Père Bougerel de l’Oratoire,

Paris, 1737, p. 14, it is related that during the month of September

1621, while promenading about three leagues’ distance from Aix in a

village named Peynier, he observed a light in the heavens to which he

gave the name of _aurora borealis_, as much on account of its location

as by reason of its resemblance to the light which precedes the rising

of the sun.

From the “History of the Royal Society,” by C. R. Weld, 1848, Vol. II.

p. 430, is taken the following, communicated by Humboldt:

“The movement of the magnetic lines, the first recognition of which is

usually ascribed to Gassendi, was not even yet conjectured by William

Gilbert; but, at an early period, Acosta, ‘from the information of

Portuguese navigators,’ assumed four lines of no declination upon the

surface of the globe.... In the remarkable map of America appended to

the Roman edition of the Geography of Ptolemy in 1508, we find, to

the north of Gruentland (Greenland), a part of Asia represented and

the magnetic pole marked as an insular mountain. Martin Cortez, in

the ‘Breve Compendio de la Sphera’ (1545), and Livio Sanuto, in the

‘Geographia di Tolomeo’ (1588), place it more to the south. Sanuto

entertained a prejudice, which, strange to say, has existed in later

times, that a man who should be so fortunate as to reach the magnetic

pole (_Il calamitico_) would then experience _alcun miracoloso

stupendo effecto_” (“Cosmos,” translated under the superintendence of

Col. Sabine, Vol. II. p. 280). In a footnote to the Otté translation of

Humboldt, 1859, Vol. V. p. 58, it is stated that _calamitico_ was the

name given to the instruments in consequence of the first needles for

the compass having been made in the shape of a frog.

In Gilbert’s “De Magnete,” allusion is made to Martinus Cortez, Book

I. chap. i., also Book III. chap. i. and Book IV. chap. i.,[43] and to

Livio Sanuto in Book I. chap. i., also in Book IV. chaps. i. and ix. In

these several passages, Gilbert tells us that Martinus Cortez holds the

loadstone’s seat of attraction to be beyond the poles, and he states

the views of other writers in this respect, citing more particularly

T. de Bessard (author of “Le Dialogue de la Longitude”), Jacobus

Servertius (who wrote “De Orbis Catoptrici”), as well as Robert Norman,

Franciscus Maurolycus, Marsilio Ficino, Cardan, Scaliger, Costa and

Petrus Peregrinus (M. J. Klaproth, “Lettre à M. le Baron de Humboldt,”

Paris, 1834, pp. 16–17, 37).

REFERENCES.--Enfield, “Hist. Phil.,” Vol. III. p. 430; “Le

Cosmos” for May and June 1859, containing a very interesting

series entitled, “Les Armées Météores”; Lardner, Vol. II. p.

113; Humboldt, “Cosmos,” 1859–1860, Vol. II. p. 335, and Vol. V.

pp. 146–153; Julius Cæsar at A.D. 1590; Houzeau et Lancaster,

Vol. II. p. 146; “Mém. de l’Acad. Royale des Sciences,” Vol. X.

p. 737; “Phil. Hist. and Memoirs of the Royal Acad. of Sc.,”

Vol. II. p. 281; “Geschichte der Mathematik,” Vol. IV. p. 474.

=A.D. 1632.=--Galileo (Galileo Galilei), Italian philosopher and

mathematician, publishes his celebrated “Dialogo sopra i due massimi

sistemi del mondo tolemaico e copernicano,” 4to, Fiorenza, from p. 88

of which is extracted the following passage:

_Sagredus_: “You remind me of a man who offered to sell me a secret for

permitting one to speak, through the attraction of a certain magnet

needle, to someone distant two or three thousand miles, and I said to

him that I would be willing to purchase it, but that I would like to

witness a trial of it, and that it would please me to test it, I being

in one room and he being in another. He told me that, at such a short

distance, the action could not be witnessed to advantage; so I sent

him away and said that I could not just then go to Egypt or Muscovy to

see his experiment, but if he would go there himself I would stay and

attend to the rest in Venice.”

This _Sagredus_ (Iohannes Franciscus), or Sagredo (Giovanni Francisco),

besides being “a great magneticall man,” was a noble Venetian, even a

doge, and had represented his country as ambassador at several courts.

We read in Mr. Conrad W. Cooke’s very able article on William Gilbert

of Colchester, originally printed in London “Engineering,” that this

same _Sagredus_ was the intimate friend of Galileo, and that, together

with the powerful Sarpi, he used the whole might of his name and

influence to protect the great philosopher and mathematician from the

attacks of the clerical party. Pietro Sarpi, otherwise known as Father

Paul, was, as already shown, a most illustrious Venetian scholar, who

attained great proficiency in the medical and physiological sciences

as well as in mathematics and in natural philosophy. _Sagredus_ made

several meritorious researches in magnetism, and, while on a voyage

to Aleppo, ascertained the declination of the magnetic needle at that

place. As a tribute to the scientific attainments of _Sagredus_,

Galileo gave his name to one of the characters in his “Systema

Cosmicum,” and many references to the work by William Gilbert are put

into the mouth of _Sagredus_.

In further illustration of Galileo’s appreciation of Gilbert, the

following is quoted from the great astronomer’s own writing: “I

extremely admire and envy the author of ‘De Magnete.’ I think him

worthy of the greatest praise for the many new and true observations

which he has made, to the disgrace of so many vain and fabling authors,

who write not from their own knowledge only, but repeat everything

they hear from the foolish and vulgar, without attempting to satisfy

themselves of the same by experience; perhaps that they may not

diminish the size of their books” (Drinkwater’s “Life of Galileo”).

Galileo had also published, in 1630, the first edition of his “I

discorsi e demonstrazioni ...” which Lagrange considers to be Galileo’s

most substantial title to scientific glory.

REFERENCES.--Galileo’s Biography in “Engl. Cycl.,” Vol. III.

pp. 13–17; Miller, “Hist. Phil. Illust.,” London, 1849, Vol.

III. p. 203, note; Nelli, “Vita,” 1793; Libri, “Hist. des Sc.

Math.,” Paris, 1838, Vol. IV. pp. 157–294, 473–484; Houzeau et

Lancaster, “Bibliog. Générale,” Vol. I. part i. pp. 655–657

for an analyzation of the works of Galileo, also Vol. II. pp.

137–145, 1576–1578; Wm. Whewell, “Phil. of the Ind. Sc.,”

London, 1840, Vol. II. pp. 379–383; Guillaume Libri, “Histoire

des Sc. Math.,” Halle, 1865, Vol. IV. pp. 157–302, and the

notes; “Journal des Savants” for September and October 1840,

for March and April 1841, for July to November 1858, for

September 1868 and for October 1877; “Geschichte der Mathem.,”

Vol. IV. pp. 4, 173, etc.; Larousse, “Dict.,” Vol. VIII. p. 954;

“La Grande Encycl.,” Vol. XVIII. pp. 383–385; “Biog. Gén.,”

Vol. XI. pp. 252–267; Fabroni (A.), “Vitæ Italorum,” 1778–1805,

also “Elogi d’Illustri Italiani,” 1786–1789; likewise the very

numerous entries concerning Galileo’s history, his Opponents,

Supporters and School, which appear at pp. 331–357, Part I. of

Libri’s “Catalogue,” published in 1861. Consult also “Galileo,”

by Ed. S. Holden, in the “Popular Sc. Monthly” for January,

February, May and June 1905; “Bibliot. Brit.,” Vol. XVI. N.S.,

1821, pp. 3–21, 79–100, for an account of the life of Galileo

by M. G. B. Clément de Nelli; “Journal des Sçavans,” Vol. LXX.

for 1721, p. 350 in his “Saggiotore”; “Imperial Dictionary of

Universal Biography,” published by Wm. McKenzie, London, pp.

536–539, giving an account of Galileo’s other discoveries.

=A.D. 1635.=--Delambre (J. B. J.) (1749–1822), professor of

astronomy at the Royal College of France, refers (Vol. II. p. 545

of his “Histoire de l’Astronomie Ancienne,” 1817) to the mention

made in “Procli Diadochi Paraphrasis Ptolem.,” lib. iv. “de siderum

effectionibus,” 1635, p. 20, of the notion long current, especially

along the shores of the Mediterranean, “that if a magnetic rod be

rubbed with an onion, or brought into contact with the emanations of

the plant, the directive force will be diminished, while a compass thus

treated would mislead the steersman.”

REFERENCES.--Humboldt, “Cosmos,” 1859, Vol. V. p. 156, also

the entry at A.D. 1653. See likewise Whewell, “Hist. of the

Ind. Sc.,” Vol. I. pp. 442, 443, 447, and the biography in the

Supplement of the “English Cyclopædia,” pp. 539–541; “Journal

des Savants,” for April 1828.

=A.D. 1635.=--Gellibrand (Henry), prominent English mathematician,

professor of geometry and the successor of Edmund Gunter (A.D. 1624),

in the chair of astronomy at Gresham College, publishes his discovery

of the _secular variation of the declination_. The credit of this

discovery has been by many given to John Mair. The _diurnal and horary

variation_ was found by Graham in 1722, and the _annual variation_ was

discovered by Cassini, 1782–1791.

Gellibrand’s discovery is published in a small quarto pamphlet

entitled “A discourse mathematical on the variation of the magneticall

needle--together with the admirable diminution lately discovered,” and

is the result of his study of the observations made by Burrough and

Gunter as well as of observations made by himself, all showing that the

north-east of the needle was gradually moving to the westward.

Mention has already been made of the fact that the _variation of the

variation_ was at this period attracting the attention it deserved,

and it is worth while giving here an account of the discovery in the

author’s own words:

“Thus, hitherto, according to the Tenents of all our Magnetical

Philosophers, we have supposed the variations of all particular places

to continue one and the same. So that when a Seaman shall happly return

to a place where formerly he found the same variation, he may hence

conclude he is in the same former longitude. For it is the assertion

of Mr. Dr. Gilbert’s _Variatio unicuiusq; loci constans est_, that

is to say, the same place doth always retaine the same variation.

Neither hath this assertion, for ought I ever heard, been questioned

by any man. But most diligent magneticall observations have plainely

offered violence to the same, and proved the contrary, namely, that the

variation is accompanied with a variation.”

=A.D. 1637.=--Bond (Henry), Professor of Mathematics in London,

and who appears in one of his treatises as “a famous teacher of the

art of navigation,” is the author of the “Seaman’s Kalendar ... with a

discovery of the ... secret of longitude ...” of which other editions

appeared during 1640 and 1696.

This was followed by many papers on the variation (the most important

of which are to be found in _Phil. Trans._ for 1668, 1672, 1673)

and, during 1678 by “The Longitude not found, or an answer to a

treatise written by H. B. ...” This treatise was in a sixty-five page

pamphlet which had been issued by Mr. Bond’s father during 1676, under

caption: “The Longitude Found; or a treatise shewing an easie and

speedy way, as well by Night as by Day, to find the Longitude, having

but the Latitude of the Place and the Inclination of the Magneticall

Inclinatorie Needle ...” wherein he explains his discovery of the

progress of the deviation of the compass and foretells the variations

for London, 1663 to 1716. This treatise led to the controversy with

Peter Blackborrow (Beckborrow), the title to whose published work

reads: “The Longitude not found: or an answer to a treatise written by

H. Bond, senior, shewing a way to find the longitude by the magnetical

inclinatory needle: wherein is proved that the longitude is not nor

cannot be found by the magnetic inclinatory needle.”

As Humboldt remarks, the resulting controversy, together with Acosta’s

view that there were four lines of no variation which divided the

earth’s surface, may, as already stated, have had some influence on

the theory advanced, in 1683, by Edmund Halley, of four magnetic poles

or points of convergence (“Cosmos,” 1859–1860, Vol. I. p. 193, note;

Vol. II. pp. 280–281, note; Vol. V. p. 58; also Humboldt’s “Examen

Critique de l’Histoire de la Géographie,” Vol. III. p. 60. See likewise

the _Phil. Trans._ for October 19, 1668, p. 790, and for 1673, Vol.

VIII. p. 6065, also following abridgments: Hutton, Vol. II. p. 78, and

Lowthorp Vol. II. p. 610).

REFERENCES.--Walker, “Magnetism,” Chap. I; John Pell, “Letter of

Remarks on Gellibrand’s Math. Disc.,” 1635; “Annales de Chimie

et de Physique,” Mars 1902, Vol. XXV. pp. 289–307; Humboldt,

“Cosmos,” 1859, Vol. V. pp. 61, 116; Whewell, “Hist. of the

Ind. Sc.,” 1859, Vol. II. p. 219; G. Hellmann, “Neudrucke von

Schriften,” No. 9; Baddam’s abridgments of the _Phil. Trans._,

1739, Vol. IV. p. 102.

=A.D. 1641.=--Wilkins (John), Bishop of Chester in the reign of

Charles II, publishes the first edition of “Mercury, or the secret

and swift messenger, showing how a man, with privacy and speed, may

communicate his thoughts to a friend at any distance.”[44]

In the above, he thus alludes to the possibility of making a

contrivance similar to our modern phonograph: “There is another

experiment ... mentioned by Walchius, who thinks it possible so to

contrive a trunk or hollow pipe that it shall preserve the voice

entirely for certain hours or days, so that a man may send his words

to a friend instead of his writing. There being always a certain space

of intermission, for the passage of the voice, betwixt its going into

these cavities and its coming out; he conceives that if both ends were

seasonably stopped, while the sound was in the midst, it would continue

there till it had some vent. _Huic tubo verba nostra insusurremus,

et cum probe munitur tabellario committamus_, etc. When the friend

to whom it is sent shall receive and open it, the words shall come out

distinctly, and in the same order wherein they were spoken. From such

a contrivance as this [saith the same author] did Albertus Magnus make

his Image, and Friar Bacon his Brazen Head, to utter certain words.”

In the eighteenth chapter, he makes suggestions for “a language that

may consist of only tunes and musical notes, without any articulate

sound.”

He had previously described a novel mode of telegraphing by the use of

only three torches (or lights), to designate the twenty-four letters of

the alphabet. These letters were, according to the plan of Joachimus

Fortius, to be placed in three classes of eight each. One torch

indicated Class I, two torches Class II, three torches Class III, and

the number of the letter was shown by the number of times a torch was

elevated.

Bishop Wilkins also described a method of telegraphing by means of two

lights attached to long poles, which, he says, “for its quickness and

speed is much to be preferred before any of the rest.” To interpret

messages at long distances, he suggested the use of the then newly

invented telescope; which he called “Galileus his perspective.”

REFERENCES.--The third edition of above-named work, Chap. XVII.

pp. 71, 72, also the fifth edition of Wilkin’s “Mathematical

Magick,” London, 1707, Chap. XIII. pp. 147–150, “concerning

several attempts of contriving a perpetual motion by magnetical

virtues.” Likewise Whewell, “Hist. of the Ind. Sc.,” 1859, Vol.

I. pp. 332, 395; Mendoza, “Tratado de Navegacion,” Vol. II.

p. 72; Alex. Chalmers, “Gen. Biog. Dict.,” London, 1811, Vol.

XXXII. pp. 74–82.

=A.D. 1641.=--Kircher (Athanasius), a German writer on physical

and mathematical science (1601–1680), member of the Order of Jesuits,

possessed of immense erudition and believing in the magnetism of all

things, speaks in his “Magnes sive de arte magnetica” (Book II. pt. iv.

chap. v.), of the recently advanced idea of being able to correspond

at short distances by employing two spherical vessels bearing the

letters of the alphabet, each of the letters having suspended from it a

magnetized figure attached to a vertical wire.

He likewise alludes to Gellibrand’s discovery, A.D. 1635,

of which he was informed by John Greaves, the eminent English

mathematician, and he communicates a letter received from the learned

French philosopher, le Père Marin Mersenne, containing a distinct

account of the same.

His definition of universal magnetism, according to Madame Blavatsky,

is very original, for he contradicted Gilbert’s theory that the earth

was a great magnet. He asserted that, although every particle of matter

and even the intangible “powers” were magnetic, they did not themselves

constitute a magnet. _There is but one Magnet in the universe, and

from it proceeds the magnetization of everything existing._ This

magnet is, of course, what the Kabalists term the central Spiritual

Sun, or God.... He demonstrates the difference between mineral

magnetism and zoömagnetism, or animal magnetism, and says that the sun

is the most magnetic of all bodies.... It imparts the binding power to

all things falling under its direct rays (“Isis Unveiled,” pp. 208–210).

Another Jesuit, Jacobo Grandamico (1588–1672), published in 1645, “Nova

demonstratio immobilitatis terræ petita ex virtute magnetica,” wherein

he shares fully the views of Niccolas Cabæus, Athanasius Kircher,

Vincentus Leotaudus and others of the same Order relative to the

earth’s magnetism (Larousse, “Dict.,” Vol. VIII. p. 1445).

REFERENCES.--“Journal des Sçavans” pour 1665 et 1666, pp.

519–525, 571–578; “Nouveau Larousse,” par Claude Augé, Paris,

Vol. V. p. 485; “Salmonsen ... konversationsleksikon,” 1900, p.

480; Van Swinden, “Recueil,” 1784, Vol. II. pp. 352, 361, 394,

and the different works named in Ronalds’s “Catalogue,” pp.

266–267; ninth ed. “Encycl. Brit.,” Vol. XIV. pp. 93–94.

=A.D. 1644.=--Digby (Sir Kenelme), the very famous Englishman to whom

allusion has already been made under the B.C. 600–580 entry, publishes,

in Paris, “Two Treatises, in the one of which the Nature of Bodies:

in the other, the nature of Man’s Soule is looked into: in Way of

Discovery of the Immortality of Reasonable Soules.”[45] In a chapter of

this work, entitled “Of the lodestone’s generation and its particular

motions,” appears the following interesting reference to Gilbert’s work

and reputation: “But to come to experimentall proofes and obseruations

vpon the loadstone by which it will appeare that these causes are well

esteemed and applyed, we must be beholding to that admirable searcher

of the nature of the loadstone, Doctor Gilbert: by means of whom and of

Doctor Haruey, our nation may claim euen in this latter age as deserued

a crowne for solide Philosophicall learning as for many ages together

it hath done formerly for acute and subtile Speculations in Diuinity.

But before I fall to particulars, I thinke it worth warning my

Reader, how this great man arriued to discouer so much of Magneticall

Philosophy; that he, likewise, if he be desirous to search into nature,

may, by imitation, advance his thoughts and knowledge that way. In

short, then, all the knowledge he gott of this subject was by forming

a little loadstone into the shape of the earth. By which meanes he

compassed a wonderful designe, which was to make the whole globe of the

earth maniable; for he found the properties of the whole earth in that

little body; which he therefore called a Terrella, or little earth;

and which he could manage and trye experiences vpon att his will. And,

in like manner, any man that hath an ayme to aduance much in naturall

sciences, must endeauour to draw the matter he inquireth of, into some

such modell, or some kinde of manageable methode; which he may turne

and winde as he pleaseth. And then lett him be sure, if he hath a

competent vnderstanding, that he will not misse of his marke.”

REFERENCES.--“The Private Memoirs of Sir Kenelme Digby,

Gentleman of the Bedchamber of King Charles I,” London, 1827;

“Dict. of Nat. Biog.,” Vol. XV. pp. 60–66; “New Gen. Biog.

Dict.,” London, 1850, Vol. XI. p. 390; “Gen. Biog. Dict.” of

Alex. Chalmers, London, 1811, pp. 70–78; “Emerson’s Works,”

London, 1873, Vol. II. p. 35; “The Library” for April 1902, has,

at pp. 131–132, the arms of the Digbys.

=A.D. 1644.=--Descartes (René), a prominent French philosopher

and mathematician, publishes his “Principia Philosophiæ,” divided

into four parts; the first giving an exposition of the principles of

all human knowledge, the second treating of the principles of natural

things, and the third and fourth parts developing his theory of

vortices. His main idea was that a rush of subtle matter passes very

rapidly through the earth from the equator towards each pole, being

opposed by magnetic substances throughout its passage and that the sun

is the centre of a vortex of an ethereal fluid, whose whirling motion

produces the revolution of planets about the sun, or around the fixed

stars. Moreover, as Noad states it, “the vortex moves with the greatest

facility in a particular direction, one of its ends being always turned

toward the north.”

One of the most prominent fellow-students of Descartes was Marin

Mersenne, who joined the religious Order of “Minimes,” and who, after

publishing in 1634 and 1639 “Les Mécaniques de Galilée” and “Nouvelles

Découvertes de Galilée,” brought out, during the years 1644 and 1647,

his well-known “Cogitata physico-mathematica,” which, Montucla says,

contains _un océan d’observations de toutes espèces_ ... and embraces

a very interesting treatise on navigation besides many letters from

leading scientists of that period not elsewhere to be found.

REFERENCES.--“La grande Encyclopédie,” Vol. XXIII. pp. 730–731;

Larousse, “Dict.,” Vol. XI. p. 94; “Biographie Générale,” Vol.

XXXV. pp. 118–123; “The English Cyclopædia,” Vol. IV. p. 206;

Alex. Chalmers, “Gen. Biog. Dict.,” London, 1811, Vol. XXII.

pp. 81–83; “Biographie Universelle,” Vol. X. pp. 465–473;

Whewell, “Hist. of the Ind. Sc.,” Vol. I. pp. 323, 328, 338,

339, 343, 354, 387, 423, 429, 430; Vol. II. p. 220; likewise

pp. 320 and 390 of Vol. I. relative to Le Père Marin Mersenne

and pp. 391 and 423 concerning the “Traité de Physique” of

James Rohault; Playfair’s Fourth Dissertation in the eighth

edition of the “Encycl. Britann.”; “Essai théorique ... des

connaissances humaines,” par G. Tiberghien, Bruxelles, 1844,

Vol. I. pp. 472–495; Dr. W. Windelband, “History of Philosophy,”

New York, 1893, pp. 380–381, 391–396; Dr. F. Ueberweg, “History

of Philosophy,” New York, 1885, Vol. II. pp. 41–55; Alfred

Weber, “History of Philosophy,” translated by Frank Thilly, New

York, 1896, pp. 305–323; Ruard Andala, “Descartes in reality

the overturner of Spinosism and the architect of experimental

Philosophy”; Erasmus Bartholinus, “De Cometis,” Copenhagen,

1664–1665 (“Biog. Univ.”; Weidler, p. 508) Mahaffy, 1880;

Houzeau et Lancaster, “Bibl. Gen.,” Vol. II. for Descartes, p.

119, and for Mersenne, p. 204; “Journal des Savants” for Feb.

1826, p. 103, for Feb. 1827, p. 110, also for Aug.-Oct. 1850,

Dec. 1860, Jan.-Feb. 1861, Oct.-Nov. 1869, Feb., April and July

1870, Mar.-April 1880, Aug. 1884, April 1898, Feb. 1899.

=A.D. 1646.=--Browne (Sir Thomas), an eminent English physician

and writer, publishes the well-known treatise “Pseudodoxia Epidemica,

or Inquiries into Vulgar and Common Errors,” which ran through six

editions in twenty-seven years, and upon which his fame is principally

established.

With regard to the possibility of such a magnetic telegraph as Strada

speaks of he says (Book II. chap. iii.): “The conceit is excellent

and, if the effect would follow, somewhat divine; whereby we might

communicate like spirits, and confer on earth with Menippus in the

moon. And this is pretended from the sympathy of two needles, touched

with the same loadstone, and placed in the centre of two abecedary

circles or rings, with letters described round about them, one friend

keeping one and another keeping the other, and agreeing upon the hour

when they will communicate, at what distance of place soever, when one

needle shall be removed unto another letter, the other, by wonderful

sympathy, will move unto the same.”

As the result of experiment, he found that “though the needles were

separated but half a span, when one was moved the other would stand

like the pillars of Hercules, and if the earth stand still, have surely

no motion at all.... By electrical bodies,” he says, “I understand not

such as are metallical, mentioned by Pliny and the ancients; for their

_electrum_ was a mixture made of gold, with the addition of a fifth

part of silver; a substance now as unknown as true _aurichalcum_, or

_Corinthian_ brass, and set down among things lost by Pancirollus. Nor

by electric bodies do I imagine such only as take up shavings, straws

and light bodies, amongst which the ancients placed only _jet_ and

_amber_, but such as, conveniently placed unto their objects, attract

all bodies palpable whatsoever. I say conveniently placed, that is, in

regard of the object, that it be not too ponderous or any way affixed;

in regard of the agent, that it be not foul or sullied, but wiped,

rubbed and excitated; in regard of both, that they be conveniently

distant, and no impediment interposed. I say, all bodies palpable,

thereby excluding fire, which indeed it will not attract, nor yet

draw through it, for fire consumes its effluxions by which it should

attract.”

The different chapters of this second book treat of the loadstone, of

bodies magnetical and electrical, of magnetical rocks and attractive

mountains, and also make allusion to the cross on the church of St.

John in Ariminium, to the reported magnetical suspension of Mahomet’s

tomb, etc. etc.

At pp. 64, 81 and 87 of Chap. II he says: “Neither is it onely true,

what Gilbertus first observed, that irons refrigerated North and

South acquire a directive faculty; but if they be cooled upright and

perpendicularly, they will also obtain the same.... Now this kind

of practice, Libavius, Gilbertus and lately Swickardus, condemn, as

vain and altogether unuseful; because a loadstone in powder hath no

attractive power; for, in that form, it omits the polarity and loseth

those parts which are the rule of attraction.... Glasse attracts but

weakely though cleere, some slick stones and thick glasses attract

indifferently; Arsenic not at all; Saltes generally but weakely, as Sal

Gemma, Allum and also Talke, nor very discoverably by any frication;

but, if gently warmed at the fire and wiped with a dry cloth, they will

better develop their Electricities.”

At Chapter XVII of the seventh book of the above-mentioned treatise,

Browne makes allusion to “the story of Frier Bacon that made a Brazen

Head to speak these words: “_Time is_....”

REFERENCES.--“Library of Literary Criticism,” Chas. Wells

Moulton, Vol. II. p. 339–345; “Fortnightly Review,” for Oct.

1905, pp. 616–626, “Sir Thomas Browne and his Family”; Edmund

Gosse, in the “English Men of Letters Series”; Browne’s “Letter”

inserted in the “Biographia Britannica,” also his entire works,

recognized as an encyclopædia of contemporary knowledge, and

which were published in four octavo volumes by Simon Wilkins,

F.S.A., London, 1836.

=A.D. 1653.=--In the third edition of “The Jewell House of Arte and

Nature,” by Sir Hugh Plat, originally published in 1594, and wrongly

attributed in Weston’s “Catalogue” to Gabriel Plattes, is to be found

the following allusion to the loadstone: “And though the adamant be the

hardest of all stones, yet is it softened with Goa’s blood and there

is a special antipathy between that and the loadstone, which is of the

colour of rusty iron, and hath an admirable vertue not onely to draw

iron to it self, but also to make any iron upon which it is rubbed to

draw iron also, it is written notwithstanding that being rubbed with

the juyce of Garlick, it loseth that vertue and cannot then draw iron,

as likewise if a Diamond be layed close unto it.”

This “special antipathy” of garlick, and of the diamond--whether or not

the latter be softened with Goa’s (goat’s) blood--is treated of very

fully by many other authors, notably:

Pliny, “Nat. Hist.,” Holland tr. 1601, Chap. IV. p. 610;

Plutarch, “Quæstones Platonicæ,” lib. vii. cap. 7; Claudius

Ptolemæus, “Opus Quadripartitum,” lib. i. cap. 3; St. Augustine,

“De Civitate Dei,” lib. xxi.; Bartholom. de Glanvilla, “Liber de

Proprietatibus Rerum,” lib. xvi.; Pietro di Abano, “Conciliator

Differentiarum,” 1520, pp. 72–73, or the Venice edition of 1526,

cap. 51; Joannes Ruellius, “De Natura Stirpium,” 1536, pp. 125,

530; Ibn Roschd’s “Comment on Aristotle,” 1550, T. IV. p. 143t;

Cardinal de Cusa, “Opera,” 1565, p. 175; C. Julius Solinus,

“De Memorabilibus,” cap. 64; Walter Charleton, “A Ternary of

Paradoxes,” London, 1650, pp. 40–41; Thomas Browne, “Pseudodoxia

Epidemica,” 1658, p. 74; G. B. Porta, “Naturall Magick,” 1658,

Chap. XLVIII and Chap. LIII--from both of which chapters

extracts appear at the A.D. 1558 entry; “Journal des Savants”

for January 1894; Chas. de Rémusat, “Hist. de la Philos.,”

Paris, 1878, Vol. II. p. 187.

Rohault--at p. 186 of his 1728 “Syst. of Nat. Phil.”--says: “As to what

some writers have related, that a loadstone will not attract iron if

there be a diamond near and that onions and garlic will make it lose

its vertue; these are contradicted by a thousand experiments which I

have tried. For I have shown that this stone will attract iron through

the very thickest diamonds and through a great many thick skins which

an onion is made up of.”

REFERENCES.--“Dict. of Nat. Biography,” Vol. XLV. pp. 407–409,

giving many particulars; J. B. J. Delambre, at A.D. 1635. For

Gabriel Plattes, see the same “Dict. of Nat. Biography,” Vol.

XLV. p. 410.

=A.D. 1657.=--Schott (Gaspar)--P. Gaspar Schott--a German Jesuit

who was sent to teach natural philosophy and mathematics at Palermo,

Sicily, is the author of several very curious works on physics, of

which the most important alone will here be noted.

“Magiæ Universalis Naturæ et Artis,” etc., appeared at Herbipoli in

1657, 1658, 1659. In the first book of the fourth volume (or part) he

indicates, according to Kircher, whom he had met while in Rome, the

means of conveying one’s thoughts at a distance by the loadstone, and

he alludes to the speaking head constructed by Albertus Magnus, while,

in the third and fourth books of the same volume, he gives a long

treatise on the loadstone as well as an account of numerous experiments

made with it.

“De Arte Mechanica,” etc. (“Mechanicæ,” etc.), Herbipoli, 1657–1658,

contains, in Part II. class i. p. 314, the first published notice of

Von Guericke’s experiments.

“Physica Curiosa sive Mirabilia Naturæ,” etc., Herbipoli, 1662 (which

may justly be considered a continuation of the “Magiæ Universalis”),

treats in the eleventh book of St. Elmo’s fire, thunder and meteors in

general.

“Technica Curiosa sive Mirabilia Naturæ,” etc., Herbipoli, 1664,

alludes, in the first two books, to the experiments made by Von

Guericke and by Boyle, and gives the contents of eight letters written

him by the first named.

“Schola Steganographica,” etc., Norimbergæ, 1665, gives, at pp.

258–264, a description of the dial telegraph of Daniell Schwenter.

“Jocoseriorum Naturæ et Artis,” etc., published about 1666, alludes to

the “Thaumaturgus Mathematicus” of Gaspar Ens, published at Cologne,

1651, as well as to the “Deliciæ Physico-Mathematicæ” of Daniell

Schwenter and Geo. Philippi Harsdoerffer (Senator of Nuremberg), to

“La Récréation Mathématique” of Jean Leurechon, and to the works of

Cardan, Mizauld, Aldrovandi and others.

REFERENCES.--“Notice Raisonnée des Ouvrages de Gaspar Schott,”

par M. L’Abbé Mxxx de St. Léger de Soissons, Paris, 1785, pp. 6,

31, 32, 37, 44, 70; Muirhead’s translation of Arago’s Eloge de

James Watt, London, 1839, p. 51.[46]

=A.D. 1660.=--Guericke (Otto von), a burgomaster of Magdeburg,

Prussian Saxony, constructs the first frictional electric machine. It

consisted of a globe of sulphur, cast in a glass sphere, and mounted

upon a revolving axis, which when rubbed by a cloth pressed against

it by the hand, emitted both sound and light. It was Guericke who

“heard the first sound and saw the first light in artificially excited

electricity.” He proved that light bodies, when attracted by an excited

electric, were immediately repelled by the latter and became incapable

of a second attraction until touched by some other body; also that

light bodies develop electrical excitation when suspended within the

sphere of an excited electric.

REFERENCES.--“Experimenta Nova Magdeburgica,” 1672, lib.

iv, cap. 15, p. 147, also all relating to the sulphur globe

reproduced from the “Experimenta Nova” at end of Figuier’s

“Exposition et Histoire,” etc., Vol. IV. Paris, 1857; Moncony,

Voyages, 1665; Schott (Gaspar), “Technica Curiosa,” etc.,

Norimbergæ, 1664; “Abhandlungen zur Geschichte der Mathem.,”

Leipzig, 1898, Vol. VIII. pp. 69–112, for the two articles

by Ferdinand Rosenberger on the development of the electric

machine, etc., from the time of Von Guericke.

=A.D. 1660.=--At the meeting of the English Royal Society, held

June 5, 1660, Magnetical Remedies were discoursed of. Sir Gilbert

Talbot promised to bring in what he knew of _sympatheticall

cures_, and those who possessed any _powder of sympathy_ were

requested to fetch some at the next meeting.

=A.D. 1661.=--Somerset (Edward), second Marquis of Worcester, an

English inventor, announces, in his “Century of Inventions” that

he has discovered “a method by which at a window as far as the eye

can discover black from white, a man may hold discourse with his

correspondent, without noise made or notice taken; being, according

to occasion given, or means afforded, _ex re nata_, and no need of

provision beforehand: though much better if foreseen, and course taken

by mutual consent of parties.” This method, he asserts, he can put

into practice “by night as well as by day, though as dark as pitch is

black.”

REFERENCES.--Dircks’ “Life of Worcester,” p. 357; “Dictionary of

National Biography,” Vol. LIII. pp. 232–237.

=A.D. 1662.=--Rupert (Prince Robert), of Bavaria, son of Frederick

V, elector palatine, and one of the founders of the Royal Society of

London, is credited with the discovery of the curious glass bubbles

called “Rupert’s drops.” These are merely drops of glass thrown, when

melted, into water, and thus becoming suddenly consolidated into a

shape somewhat resembling the form of a tear. The globular end may be

subjected to quite a smart stroke without breaking, but if a particle

of the tail is nipped off, the whole flies into fine powder with almost

explosive violence.

“Mr. Peter did show us the experiment (which I had heard talked of) of

the chymicall glasses, which break all to dust by breaking off a little

small end; which is a great mystery to me” (Samuel Pepys, “Diary,”

January 13, 1662).

Sir David Brewster discovered that the fracture of these unannealed

drops was accompanied by the evolution of electrical light, which

appears even when they are broken under water. Mr. Bennet observed

that when one of the drops was placed upon a book, the latter was

electrified negatively.

REFERENCES.--The articles on “Annealing,” “Optics,” and

“Electricity” in the “Encyclopædia Britannica”; also the

biography in “Penny Cycl.,” Vol. XX. pp. 226–227; Le Cat,

“Memoir,” London, 1749–1750, or _Philos. Trans._, XLVI. p. 175.

=A.D. 1665.=--Grimaldi (Francesco Maria), Italian philosopher

(1618–1663), member of the Order of Jesuits and an associate of the

astronomer Giovanni Battista Riccioli (at A.D. 1270) is the author of

the important work “Physico mathesis de Lumine ...” which cites the

discovery of magnetism produced by the perpendicular holding of an iron

bar.

REFERENCES.--_Phil. Trans._ for 1665; “Engl. Cycl.,” article

“Biography,” Vol. CXI. p. 207; Larousse, “Dict.,” Vol. VIII,

p. 1531. And, for Riccioli’s works, see Houzeau et Lancaster,

“Bibliog. Gén.,” Vol. III. p. 238; “Journ. des Sçavans” pour

1665 et 1666, pp. 642–647.

=A.D. 1665.=--Glanvill (Joseph), an eminent English divine and

philosopher, Chaplain to King Charles II and F.R.S., sometimes

called “Sadducismus Triumphatus Glanvill,” endorses in his “Scepsis

Scientifica” (“the vanity of dogmatizing recast”)--published originally

in 1661--the views advanced previously by the Jesuit Leurechon, and,

after discussing the objections of Sir Thomas Browne, expresses the

belief that “to confer at the distance of the Indies by sympathetic

conveyances may be as usual to future times as to us in literary

correspondence.”

A writer in the “Bath Chronicle” reproduced a long extract from

Glanvill’s work, the concluding sentence of which, he says, seems to

have anticipated the electric telegraph. It is as follows: “But yet

to advance another instance. That men should confer at very distant

removes by an extemporary intercourse is a reputed impossibility; but

yet there are some hints in natural operations that give us probability

that ’tis feasible, and may be compassed without unwarrantable

assistance from demoniack correspondence. That a couple of needles

equally touched by the same magnet, being set in two dials exactly

proportioned to each other, and circumscribed by the letters of the

alphabet, may effect this ‘magnale’ (_i. e._ important result)

hath considerable authorities to avouch it.

“The manner of it is thus represented: Let the friends that would

communicate take each a dial, and, having appointed a time for their

sympathetic conference, let one move his impregnate needle to any

letter in the alphabet, and its affected fellow will precisely respect

the same. So that, would I know what my friend would acquaint me with,

’tis but observing the letters that are pointed at by my needle, and

in their order transcribing them from their sympathized index, as its

motion directs; and I may be assured that my friend described the same

with his, and that the words on my paper are of his inditing. Now,

though there will be some ill-contrivance in a circumstance of this

invention, in that the thus impregnate needles will not move to, but

avert from each other (as ingenious Dr. Browne hath observed), yet this

cannot prejudice the main design of this way of secret conveyance;

since it is but reading counter to the magnetic informer, and noting

the letter which is most distant in the Abecederian circle from that

which the needle turns to, and the case is not altered.

“Now, though this desirable effect may possibly not yet answer the

expectations of inquisitive experiment, yet ’tis no despicable item,

that by some other such way of magnetick efficiency it may hereafter

with success be attempted, when magical history shall be enlarged by

riper inspections; and ’tis not unlikely but that present discoveries

might be improved to the performance.”

Glanvill is also the author of “Philosophical Considerations Touching

Witches and Witchcraft,” 1666, and of “The Sadducismus Triumphatus,”

1681.

REFERENCES.--“Dict. of Nat. Biog.,” 1908, Vol. VII. pp. 1287–8;

Larousse, “Dict.,” Vol. VIII. pp. 1294–1295; “Nature,” Vol. XVI.

p. 269; “Histoire de la Philosophie,” par Charles de Rémusat,

Paris, 1878, Vol. II. chap. xi. pp. 184–201; “The General

Biog. Dict.,” Alex. Chalmers, London, 1811, Vol. XVI. pp.

12–17; “Joseph Glanvill,” by Ferris Greenslet, New York, 1905;

“Imperial Dict. of Universal Biography,” Vol. II. p. 642.

=A.D. 1666.=--Denys (William), hydrographer, of Dieppe, observes

that the compasses placed in different parts of a vessel give different

indications (Becquerel, “Magnétisme,” p. 119; “Journal des Sçavans”

pour 1665 et 1666, p. 538).

=A.D. 1671.=--Richer (T.), French philosopher, who was sent by

the Paris Academy of Sciences to the island of Cayenne for the purpose

of determining the amount of terrestrial refraction and for other

astronomical objects, is the first to make known the electrical powers

of the _gymnotus electricus_.

REFERENCES.--Leithead, “Electricity,” Chap. XII; Fahie, “El.

Tel.,” p. 171; Bertholon, “Elec. du Corps Humain,” 1786, Vol. I.

p. 171; _Mém. de l’Acad. des Sciences_, 1677, Art. VI; Richer,

“Observations,” etc., Paris, 1679; Bancroft, at A.D. 1769;

“Cosmos,” 1859, Vol. V. pp. 23–24.

=A.D. 1671.=--Rohault (Jacques), a French philosophical writer,

and one of the earliest, ablest and most active propagators of the

Cartesian philosophy in France, publishes at Paris the first edition

of his “Traité de Physique,” at Part III. chap. viii. pp. 198–236 of

which he treats especially of amber and of the loadstone. The same

passages can be seen at Vol. II. part iii. chap. viii. pp. 163, etc.,

of Rohault’s “System of Natural Philosophy,” published in London during

the year 1723, and at the same chapter, pp. 388, etc., of “Jacobi

Rohaulti Physica,” Londini, 1718.

The latter is the last and best edition of the well-known classical

translation, originally made in 1697, by Dr. Samuel Clarke, who was the

friend of Sir Isaac Newton and chaplain to Bishop Moore, of Norwich.

Through this work Clarke introduced very many critical notes exposing

the fallacies of the Cartesian system. The “Physica” passed through

four editions as the Cambridge University textbook before it was made

to give way to the treatises of Newton.

=A.D. 1672.=--Sturm (John Christopher), a very able German

mathematician, who was for thirty-four years professor of natural

philosophy at the University of Altdorf (Franconia), and who,

after vainly attempting to satisfactorily unite the Aristotelian

and Cartesian doctrines finally adopted the Baconian philosophy,

establishes the “Collegium Curiosum” on the plan of the celebrated

Italian “Accademia del Cimento,” alluded to under the A.D.

1609 date.

The society was founded for the purpose of studying, repeating and

even modifying the most notable philosophical experiments of the

day, such as those made by Von Guericke, Boyle, Hooke and others, and

its proceedings were published in 1676 and 1685 under the title of

“Collegium Experimental sive Curiosum, etc.”

=A.D. 1673.=--Hevelius--Hevel--Hovel--Hövelke (Joannes), an eminent

Polish astronomer, member of the English Royal Society, and a great

friend more particularly of le Père M. Mersenne, of Gassendi and

of Kircher, publishes during 1673 the first part of his great work

“Machina Cœlestis”--dedicated to Louis XIV--the entire second part of

which, issued in 1679, was destroyed by fire with the exception of

seven copies. This explains its extreme scarcity. It was this work

which led to the public controversy between Hevelius and Dr. Hooke

who published, in London, during 1674 his “Animad. in Mach. Celest.

Hevelii.”

It is said that, next to John Flamsteed, Hevelius was the most accurate

observer of the heavens in his day (“The Reliquary,” London, Vol. XIV.

pp. 149–159 and Vol. XV. pp. 34–38; “Journal des Savants” for March,

June and November 1836). He had already published “De Variatione acus

magneticæ” (_Opusc. Act. Erudit. Lips._, Vol. I. p. 103), also a

report of the variations of the magnetical needle during 1670, which

can be found in the _Phil. Trans._, Vol. V. for 1670, p. 2059, or

in Hutton’s abridgments, London, 1809, Vol. I. p. 514.

REFERENCES.--Larousse, “Dict.,” Vol. IX. pp. 266–267; “Biog.

Gén.,” Vol. XXV. pp. 285–294; Delambre, “Hist. de l’Astron.

Mod.,” Vol. II. pp. 434–484; Weidler, “Hist. Astron.,” p. 485;

“Mem. Roy. Soc.,” 1739, Vol. I. p. 274.

=A.D. 1675.=--Boyle (Robert), Irish natural philosopher and

chemist, seventh son of Richard Boyle, Earl of Cork, and one of the

first members of what he calls the “Invisible” or “Philosophical”

College, which has since become the Royal Society,[47] gives, in

his “Philosophical Works,” the result of his many experiments upon

magnetism and electricity.

John Evelyn in his letter to Mr. Wotton, March 30, 1695 (“Memoirs,

Diary and Correspondence,” by Wm. Bray, London, p. 716), says of Boyle:

“It must be confess’d that he had a marvailous sagacity in finding out

many usefull and noble experiments. Never did stubborn matter come

under his inquisition but he extorted a confession of all that lay in

her most intimate recesses; and what he discover’d he as faithfully

register’d, and frankly communicated....”

Prof. Tyndall remarks (“Lecture,” February 4, 1875): “The tendency

to physical theory showed itself in Boyle. He imagined that the

electrified body threw out a glutinous or unctuous effluvium, which

laid hold of small bodies, and, in its return to the source from which

it emanated, carried them along with it.”

A few of his many characteristic remarks and observations are, however,

best given in his own words, as extracted from the “Philosophical

Works” above alluded to:

“The invention of the mariner’s needle, which giveth the direction, is

no less benefit for navigation than the invention of the sails, which

give the motion” (London, 1738, Vol. I. p. 62).

“I, with a certain body (rough diamond), not bigger than a pea, but

very vigorously attractive, moved a steel needle, freely poised, about

three minutes after I had left off rubbing it” (Vol. I. p. 508).

Speaking elsewhere of his experiments with diamonds, he says: “But when

I came to apply it (the loadstone) to one more, which look’d somewhat

duller than almost any of the rest, I found that it had in it particles

enough of an iron nature to make it a magnetical body and observed

without surprise that not only it would suffer itself to be taken up

by the strongest pole of the loadstone, but when the pole was offer’d

within a convenient distance it would readily leap through the air to

fasten itself to it.”

“I removed a piece of amber in the sunbeams till they had made it

moderately hot and then found it would attract those light bodies it

would not stir before” (Vol. I. p. 400, and Vol. III. p. 52).

“Whether from such experiments one may argue that it is but, as it

were, by accident that amber attracts another body, and not this the

amber; and whether these ought to make us question, if _electrics

may_, with so much propriety, as has been generally supposed, _be

said to attract_, are doubts, that my design does not oblige me to

examine” (Vol. IV. p. 350).

REFERENCES.--John Evelyn’s “Diary,” Letter to Mr. Wotton, March

30, 1696; Libes’ “Histoire Phil. du Progrès de la Physique,”

Paris, 1810; Boyle’s “Mechanical Origine or Production of

Electricity,” 1675; Birch, “Life of Hon. R. Boyle,” 1743–1744;

Secondat’s “Histoire d’Electricité” (Observations physiques),

1750, p. 141; Whewell, “Hist. of Ind. Sciences,” 1859, Vol. I.

pp. 395, 396. Priestley’s “History of Electricity,” 1775, pp.

5–8; M. Reael, “Observ. a. d. Magnectsteen,” 1651, alluded to

at note, p. 486, Vol. I. of Van Swinden’s 1784 “Recueil,” etc.;

Van Swinden, Vol. II. pp. 353, 359–361; “Biblioth. Britan.”

(Authors), Robt. Watt, Edinburgh, 1824, Vol. I. pp. 142–3;

Aikin’s “G. Biography,” and Martin’s “Biog. Philosophica,”

in “General Biog. Dict.,” by John Gorton, London, 1833, Vol.

I; _Phil. Trans._, Vol. VIII for 1673, p. 6101 and Hutton’s

abridg., Vol. II. p. 90; Boyle, London, 1673, “Essays of the

... Effluviums” (Subtility), pp. 38–42, 52–53; (Efficacy) pp.

18, 19, 32, 33; (Determinate Nature) pp. 21, 57; “An Essay ...

of Gems,” London, 1672, pp. 108–129; Ch. W. Moulton, “Library

of Literary Criticism,” Vol. II. pp. 416–420; “Critical Dict.

of Engl. Lit.,” S. Austin Allibone, Philad., 1888, Vol. I.

pp. 232–233; “Essays in Historical Chemistry,” T. E. Thorpe,

London, 1894, pp. 1–27; Eighth “Britannica,” V. p. 259 for notes

of Boerhaave, also the “Britannica” 1st Dissertation, p. 47,

and 4th Dissertation p. 597; “History and Heroes of the Art of

Medicine,” J. Rutherfurd Russell, London, 1861, pp. 233–246.

Consult also Boyle’s “New Exper. Physico-Mechanical,” etc.,

in which the 16th Exp. is “concerning the operation of the

loadstone”; Boyle’s “A Continuation of New Exp.,” etc., in which

the 31st Exp. is “about the attractive virtue of the loadstone

in an exhausted receiver,” and in which are “Notes, etc.,

about the atmospheres of consistent bodies,” etc., as well as

“Observations about the exciting of the electricity of bodies,”

and concerning the electrical emanations and effluviums. Boyle’s

“Tracts Containing Some Suspicions Concerning some Occult

Qualities of the Air; with an Appendix Touching Celestial

Magnets,” etc. His “Phil. Works,” London, 1744, Vol. III. pp.

65, 67 and 70, 647, etc., give “Experiments and Notes about the

Mechanical Origin or Production of Electricity.”

For full accounts of the Royal Society, alluded to above, see

the histories written by Thomas Sprat (1667), by Thomas Birch

(1756), by Thomas Thomson (1812), and by Chas. Richard Weld

(1847–1848).

=A.D. 1675.=--Picard (Jean), eminent astronomer, who succeeded

Gassendi (A.D. 1632) as professor of astronomy at the Collège

de France, is the first to observe electric light _in vacuo_.

According to Tyndall (“Lessons in Electricity,” p. 88) it was while

carrying a barometer from the Observatory to the Porte Saint-Michel

in Paris that he noticed light in the vacuous portion. Sebastien and

Cassini observed it afterwards in other barometers (see Tyndall’s

“Lecture V.” p. 91, for Priestley’s description of the electric light

_in vacuo_).

It was this same scientist who had already given, in his “Mesure de

la Terre,” 1671, Article IV, the description of the measurement of a

degree of latitude made with instruments of his own manufacture.

REFERENCES.--Humboldt, “Cosmos,” 1859, Vol. V. pp. 23, 24;

Larousse, “Dict.,” Vol. XII. p. 937; “Phil. Hist. and Mem. of

the Roy. Acad. at Paris,” London, 1742, Vol. I. pp. 208–221.

=A.D. 1675.=--Newton (Sir Isaac), prominent English mathematician

and natural philosopher, of whom Macaulay says that “in no other mind

have the demonstrative faculty and the inductive faculty coexisted in

such supreme excellence and perfect harmony,” communicates to the Royal

Society his discovery that excited glass will attract any light bodies

even to the surface opposite to that upon which it has been rubbed.

This was successfully demonstrated by the Society, January 31, 1676.

He improved the electric machine by substituting a glass globe for

the globe of sulphur made use of by both Von Guericke and Boyle, the

rubbers in every case being the hands of the operator.

He appears to have somewhat anticipated Franklin’s great discovery,

judging by the following letter he addressed, December 15, 1716, to the

Rev. Dr. Law, in Suffolk:

“Dear Doctor,” it begins, “He that in ye mine of knowledge

deepest diggeth, hath, like every other miner ye least breathing

time, and must sometimes at least come to terr; alt (terra

alta) for air. In one of these respiratory intervals I now sit

doune to write to you, my friend. You ask me how, with so much

study, I manage to retene my health. Ah, my dear doctor, you

have a better opinion of your lazy friend than he hath himself.

Morpheus is my best companion; without eight or nine hours

of him ye correspondent is not worth one Scavenger’s peruke.

My practizes did at ye first hurt my stomach, but now I eat

heartily enow, as y’ will see when I come down beside you. I

have been much amused by ye singular φενομενα resulting from

bringing a needle into contact with a piece of amber or resin

fricated on silke clothe. Ye flame putteth me in mind of sheet

lightning on a small--how very small--scale. But I shall in my

epistles abjure philosophy, whereof when I come down to Sakly

I’ll give you enow. I begin to scrawl at five mins. from nine of

ye clk, and have in writing consumed ten mins. My Lord Somerset

is announced.”

Æther, according to Sir Isaac Newton, is a thin subtile matter much

finer and rarer than air. Sometimes, it is termed by him, a subtil

spirit, as in the latter part of his “Principia,” and sometimes a

subtil ætherial medium, as in his “Optics.” By many it is supposed to

pervade all space, also the interior of solid bodies, and to be the

medium of the transmission of light and heat. The æther of Descartes

was his _materia subtilis_ or his First Element: by which he

understood a “most subtil matter very swiftly agitated, fluid, and

keeps to no certain figure, but which suits itself to the figure of

those bodies that are about it. His Second Element consists of small

Globules; that is, bodies exactly round and very solid, which do not

only, like the First Element, fill up the pores of bodies but also

constitute the purest substance of the Æther and Heaven” (Blome’s

translation of Descartes’ “Philosophy,” p. 101; R. Lovett, “The Subtil

Medium Prov’d”; _Phil. Mag._, Vol. XVIII. p. 155).

During the years 1686 and 1687 Newton composed his “Principia,” a

work which Lagrange pronounced “la plus haute production de l’esprit

humain”: “the greatest work on science ever produced” (Sir Robt. Ball),

and “which will be memorable not only in the annals of one science or

of one country, but which will form an epoch in the history of the

world.” This was published at Halley’s expense. As Brewster says (1686,

Chap. XII): “It is to Halley alone that science owes this debt of

gratitude. It was he who tracked Newton to his college, who drew from

him his great discoveries, and who generously gave them to the world.”

In the twenty-third proposition of the second book, fifth section,

Newton says: “The virtue of the magnet is contracted by the

interposition of an iron plate and is almost terminated at it, for

bodies further off are not so much attracted by the magnet as by the

iron plate.” And in Book III. prop. vi. he thus expresses himself:

“The magnetic attraction is not as the matter attracted; some bodies

are attracted more by the magnet, others less; most bodies not at all.

The power of magnetism in one and the same body may be increased and

diminished, and is sometimes far stronger for the quantity of matter

than the power of gravity; and in receding from the magnet decreases,

not in the duplicate, but almost in the triplicate proportion of the

distance, as nearly as I could judge from some rude observations.”

Newton is said to have carried in his ring a magnet weighing but three

grains, which could raise 746 grains, or nearly 250 times its own

weight. This magnet naturally excited much admiration, but is greatly

surpassed in power by that formerly belonging to Sir John Leslie,

and now in the Physical Collection at Edinburgh, weighing three and

one-half grains, and having a carrying power of 1560 grains.

REFERENCES.--Brewster’s “Life of Sir I. Newton,” pp. 307, 308;

“Dict. of Nat. Biog.,” Vol. XL. pp. 370–393; Ch. W. Moulton,

“Library of Literary Criticism,” Vol. II. pp. 710–726; “Bibl.

Britan.” (Authors), Robt. Watt, Edinburgh, 1824, Vol. II., p.

701; Harris, “Magnetism,” Vol. III. p. 11; Ninth “Britannica,”

Vol. XV. p. 274; Whewell, “Hist. of the Ind. Sciences,” 1858,

Vol. I. pp. 385–488; the interesting note at foot of p. 683

of the Fourth Dissertation in the “Encyclopædia Britannica”;

“Muspratt’s Chemistry,” Vol. II. p. 255; the English “Chemical

News” for November 1867, and January 1868, reproducing Sir David

Brewster’s letters to the London “Athenæum” and London “Times,”

likewise Dr. Crompton’s paper read before the Manchester

Literary and Philosophical Society in October 1866; _Phil.

Trans._, Vol. LXIV. Part I for 1774, p. 153: “Remarks of John

Winthrop upon ... Castillione’s Life of Sir Isaac Newton”; Dr.

Geo. Miller, “Hist. Phil. Ill.,” London, 1849, Vol. III. pp.

414–415; “Newton, sa vie et ses œuvres” in “Cosmos,” September

27, 1890 to December 13, 1890; “Journal des Savants” for April,

May and June 1832; for April 1846, March, April, May, June, July

and August 1852, October, November 1855; Houzeau et Lancaster,

“Bibl. Gén.,” Vol. II, 1882, pp. 213–214, 1586; “Hist. de la

Philosophie,” par Chas. de Rémusat, Paris, 1878, Vol. II. chap.

xii. pp. 202–222.

=A.D. 1676.=--Haward, master of several sailing vessels, and a man

of good credit (_Phil. Trans._, Vol. XI. No. 127, p. 647, of July

18, 1676), states that “being on board of the ship Albemarle, July

24, 1641 ... in latitude of Bermuda ... after a terrible clap of

thunder ... it was found that the compass card was turned around, the

N. and S. points having changed positions and, though Mr. Grofton

brought with his finger the flower-de-lys to point directly N., it

would immediately, as soon as at liberty, return to this new unusual

posture, and upon examination he found every compass (three) in the

ship of the same humour; which ... he could impute to nothing else

but the operation of the lightning or thunder mentioned.” The above

is also alluded to at p. 33 of Vol. III. of Boyle’s “Phil. Works,”

London, 1738, with this addition: “One of the compasses, pointing West,

was brought to New England, where, the glass being broke and the air

gaining entrance, it lost its virtue. But one of the others is in that

country possess’d by Mr. Encrease Mather, the North point of the needle

remaining South to this day.”

=A.D. 1677.=--At p. 14 of an exceedingly curious publication

entitled “A Rich Cabinet with a Variety of Inventions,” etc., written

by J. W. (_i. e._ John White, of London), who calls himself “a

lover of artificial conclusions,” will be found an article on “Divers

rare, conceited motions performed by a magnet or loadstone.”

=A.D. 1678.=--Redi (Francesco), well-known Italian scientist,

physician to the Grand Duke Ferdinand II, publishes his “Experimenta

circa res diversas Naturales,” wherein he is first to communicate the

fact that the shock of the _raia torpedo_ can be transmitted to

the fisherman through the line and rod connecting him with the fish.

REFERENCES.--Leithead, “Electricity,” Chap. XII; the Firenze,

1671 ed. of Redi’s “Esperienze,” etc., pp. 47–54; _Phil. Trans._

for 1673, Vol. VIII. p. 6003; _Sci. Am. Supp._, No. 457, pp.

7300–7302; Matteucci, “Recherches,” 1837 and 1867; Eschinardi

(F. della Compagnia di Gesü), “Lettera al S. Francesco Redi,”

Roma, 1681, wherein are detailed many curious experiments,

including some treating of the magnetic needle by which agency

are foretold sudden attacks of earthquakes, etc. etc.

=A.D. 1679.=--Maxwell (William)--Guillelmo Maxvello--native of

Scotland, author of “Medicina Magnetica,” offers to prove to various

medical faculties that, with certain magnetic means at his disposal,

he could cure any of the diseases abandoned by them as incurable

(Blavatsky, “Isis,” Vol. I. p. 215).

REFERENCE.--J. H. Van Swinden, “Recueil de Mémoires,” etc., La

Haye, 1784, Vol. II. p. 367.

=A.D. 1683.=--Arrais (Edoardo Madeira), who had been physician

to--João--John IV, the first Portuguese king of the house of Braganza,

is the author of this much-delayed edition of a book entitled “Arbor

Vitæ, or a physical account of the Tree of Life in the Garden of Eden.”

It treats of occult qualities under the headings of “Doubts,” of which

latter there are eight separate ones which constitute as many different

chapters, from which the following extracts will prove interesting:

“Doubt” 5, p. 45. “Doth not the fish called _Torpedo_ render the

fishes that swim over it immovable, and stupefy the fisher’s arm

with its virtue diffused along his spear?”

“Doubt” 5, p. 46. “... as also there are divers sorts of fishes

that bring numness, as our _Torpedo_ doth.”

“Doubt” 5, p. 49. “And those that travail the coasts of Brasile

make mention of another fish, which causeth numness as our

_Torpedo_ doth: whence it becomes sufficiently manifest that

there are many kinds of _Torpedoes_ to be found. But this kind

lives especially in the river Itapecuro, in the country of the

Maragnani, and it is called _Perache_, or, as Gaspar Barlæus

observed, _Puraquam_, among those Barbarians. In shape and

greatness it resembles a kind of lamprey (or Muræna); they

use to kill it by striking it with staves; but the arm of him

that strikes and then his whole body is stupefied, and shakes

presently. Of which thing, Frier Christopher Severineus, Bishop

elect of Angola is my ocular witness....”

“Doubt” 7, p. 93. “For it is evident from experience that iron

is so indisposed by some qualities that it cannot be moved by

the magnet. That fishes swimming over the _Torpedo_, enclosed in

the mud or sand for the purpose, when they come to the places

whereto the virtue of the _Torpedo_ is extended can stir no

further; by which art she catches and eats them, as Aristotle

relates (6 ‘de Hist. Animal.,’ cap. 10; and 9 ‘de Hist.,’ cap.

37).”

“Doubt” 7, p. 94. “For if amber be dulled by moisture, its

virtue cannot produce motion in straws. If the virtue of the

_Torpedo_ reach the fishes swimming over her, or the

fisher’s arm their motive power cannot produce motion.”

“Doubt” 7, p. 96. “And for this cause, the virtue of the magnet

can produce motion in iron, not in other bodies, because it

finds in it Dispositions necessary on the part of the agent

which, being present, it can operate; not in other things. And,

for the same reason, amber moves straws, not iron nor stones.”

The preface to the “Arbor Vitæ ...” is written by Richard Browner M.L.

Coll. Med., London, who translated out of Latin “The Cure of Old Age,”

by Roger Bacon, wherein he gives quite a good account of the latter’s

life and writings, and from which we extract but one passage likely

here to be of some little interest, viz. at p. 155, regarding the

component parts of a medicine: “By Amber here our author intends Amber

Gryse (a bituminous body found floating on the sea): For he calls it

Ambra and not Succinum (which is solid Amber). Besides, Succinum was

never reckoned a spice as Amber is here. And though both Ambra and

Succinum be great restorers of the animal spirits, yet the former is

more efficacious.”

The “Biographie Générale,” Vol. III. p. 348, says that Duarte Madeyra

Arraess, who died at Lisbon in 1652, was the author also of “Apologia,”

1638, of “Methodo,” 1642, and of “Novæ Philosophiæ,” 1650.

=A.D. 1683.=--Halley (Edmund), LL.D., who became English astronomer

royal, makes known his theory of four magnetic poles and of the

periodical movement of the magnetic line without declination. He states

that the earth’s magnetism is caused by four poles of attraction,

two of them being in each hemisphere near each pole of the earth. By

the word _pole_ he means a point where the total magnetic force is a

maximum, or, as he himself styles it, “a point of greatest attraction”

(Walker, “Magnetism,” p. 317, etc.).

One of the magnetic poles he places near the meridian of Land’s End,

not above 7 degrees from the North Pole, the other being about 15

degrees from the North Pole in the meridian of California, while the

two south magnetic poles are placed respectively about 16 and about

20 degrees from the South Pole of the earth, and 95 degrees west, 120

degrees east of London.

In order to test Halley’s theory, the English Government permitted him

to make three voyages in the Atlantic Ocean (1698, 1699, 1702), in

vessels of which he had the command as post-captain. Humboldt states

that these were the first expeditions equipped by any government for

the establishment of a great scientific object--that of observing one

of the elements of terrestrial force on which the safety of navigators

is especially dependent.

The result of these voyages was the construction of the first accurate

Magnetic Chart, whereon the points at which navigators have found an

equal amount of variation were connected together by curved lines. This

was the model of all charts of a similar nature since constructed.

Halley remarked upon its completion: “The nice determination of the

variation, and several other particulars in the magnetic system, is

reserved for a remote posterity. All that we can hope to do is to

leave behind us observations that may be confided in, and to propose

hypotheses which after-ages may examine, amend or refute.”

See copy of his chart in Vol. I. No. I of “Terrestrial Magnetism,” also

in Musschenbroek’s “Essais de Physique,” or, preferably, in Bouguer’s

“Traité de Navigation,” where the lines for 1700 are in red ink, while

those for 1744 are traced in black, thus readily indicating the changes

in the declination.

REFERENCES.--Cavallo, “Magnetism,” and “Nat. or Exp. Phil.,”

Vol. II. p. 273; Lloyd, “Treatise on Magnetism,” 1874, p. 102;

_Sci. Am. Suppl._, No. 224, pp. 3570, 3571; Whewell, “Hist. of

the Inductive Sciences,” 1859, Vol. I. pp. 396–8, 435–7, 450,

451, 480, 481, and Vol. II. p. 225; Giambattista Scarella, “De

Magnete,” 1759, Vol. II; also G. Casali, “Sopra la Grandine,”

etc., 1767; “The Phil. Hist. and Mem. of the Roy. Ac. of

Sciences at Paris,” London, 1742, Vol. I. p. 245; Vol. II. pp.

240–244, 270, 349; “Magnetic Results of Halley’s Expedition

(1698–1700)” in “Terrestrial Magnetism,” September 1913, pp.

113–132; Houzeau et Lancaster, “Bibl. Gén.,” Vol. II. pp.

156–7; Dr. G. Hellmann “Neudrucke von schriften,” Nos. 4 and

8; Humboldt, “Cosmos,” 1859, Vol. V. pp. 59–60; John Wallis’s

letters to Halley, London (_Phil. Trans._ for 1702–1703), p.

106; _Phil. Trans._ for 1667, 1683, 1692; “Memoirs of the Roy.

Soc.,” 1739, Vol. II. p. 195; “A Bibliography of Dr. Edmund

Halley,” by Alex. J. Rudolph, in the “Bulletin of Bibliography”

for July 1905; “Old and New Astronomy,” by Richard A. Proctor,

1892, pp. 37–38; _Phil. Trans._ Vol. XIII for 1683, No. 148,

p. 208; Vol. XVII. p. 563; Vol. XXIII. p. 1106; Vol. XXIX. p.

165; Vol. XLII. p. 155; Vol. XLVIII. p. 239, also the following

abridgments: Hutton, Vol. II. p. 624; Vol. VI, pp. 99, 112; J.

Lowthorp, Vol. II. p. 285; Reid and Gray, Vol. VI. p. 177; Eames

and Martyn, Vol. VI. pp. 28, 286; Baddam, 1745, Vol. II. pp.

195–202; Vol. III. pp. 25–32.

AURORA BOREALIS, OR NORTHERN POLAR LIGHT

Dr. Halley was the first to give (_Phil. Trans._, No. 347) a distinct

history of this phenomenon, which has certainly an electric as well as

magnetic origin, and to which Gassendi originally gave the name it now

bears, as has been stated at A.D. 1632.

According to Dr. Lardner (“Lectures,” Vol. I. p. 137), Prof. Eberhart,

of Halle, and Paul Frisi, of Pisa, first proposed an explanation of the

aurora founded upon the following: 1. Electricity transmitted through

rarefied air exhibits a luminous appearance, precisely similar to

that of the aurora borealis. 2. The strata of atmospheric air become

rarefied as their altitude above the surface of the earth is increased,

a theory which has since been countenanced by many scientists. It has

been observed, notably by Dalton, of Manchester, that the primitive

beams of the aurora are constantly in a direction parallel to that

of the dipping needle, and that the latter appears most affected

when the aurora is the brightest. Arago noticed that the changes of

inclination amounted, upon one occasion to 7’ or 8’. The discovery that

the magnetic needle was agitated during the presence of an aurora has

been ascribed to Wargentin (_Am. Journal Sc._, Vol. XXX. p. 227),

though it is claimed by the friends of Olav Hiörter (see A.D.

1740), that it was independently ascertained by the latter during the

year 1741.