one of the valuable elements of our national manufacturing superiority,
was born at Marnham in Nottinghamshire, and was the youngest of three
brothers, all of whom were remarkable men.[9] He was educated under
Dr. Clarke, at the Grammar School of Wakefield, and had he been
permitted to follow the bent of his own inclination in the choice of
a profession, would have preferred the navy; but two of his brothers
being already designed for that service, it was thought advisable that
Edmund should enter the Church. Dr. Cartwright began his academical
studies at University College, Oxford, where he was entered at fourteen
years of age, and during the vacations was placed under the private
tuition of Dr. Langhorne, the editor of 'Plutarch's Lives.'
In process of time he became distinguished for his literary abilities,
and was elected a Fellow of Magdalen College. He likewise evinced a
considerable taste for poetry, and published in 1770 a legendary tale,
entitled 'Armine and Elvira,' which went through seven editions in
little more than a year, and was greatly admired for its pathos and
elegant simplicity. Some years subsequent to this, Cartwright wrote
'The Prince of Peace,' published in 1779, and was also for several
years a principal contributor to the 'Monthly Review.'
In the year 1772 he married the daughter of Richard Whittaker, Esq.,
of Doncaster, and after his marriage resided first at Marnham, and
afterwards at Brampton in Derbyshire, to the perpetual curacy of
which he was presented by the Dean of Lincoln, Dr. Cust. It was
while attending to his clerical duties at this latter place, that
Cartwright discovered the application of yeast as a remedy for typhus
fever. In 1779 he was presented to the living of Goadby Marwood in
Leicestershire, and continued to reside there until the summer of 1796,
when he removed with his family[10] to London, as being a situation
more favourable for the cultivation of the scientific pursuits in which
he had by that time become engrossed.
Dr. Cartwright had attained the mature age of forty, before his
attention was drawn towards the subject of weaving, by the following
accidental occurrence:--In the summer of 1784, he happened to be on a
visit at Matlock, in Derbyshire, and in the company of some gentlemen
from Manchester. The conversation turned upon Arkwright's spinning
machinery; and fears were expressed by one of the company, that, in
consequence of the recent improvements, so much cotton would soon be
spun, that hands would not be found to weave it. To this the doctor
replied, that the only remedy for such an evil would be to apply the
power of machinery to weaving as well as spinning. The discussion which
ensued upon the practicability of doing this, made such an impression
on Cartwright's mind, that on returning home he determined to try and
see what he could do.
His first attempts, as might be supposed, were very clumsy, but he at
length succeeded in constructing a machine (for which he took out a
patent in 1785), which, although rude and cumbersome in its action, was
yet capable of weaving a piece of cloth. Up to this time he had never
turned his mind to anything mechanical, either in theory or practice,
and his invention was consequently susceptible of great improvement.
To accomplish this, he now examined with care the contrivances already
in use among the weavers, and availing himself of their general
principles, produced in the year 1787 a far more complete and valuable
machine, since known as the power-loom.
Shortly after he had brought his loom to perfection, a manufacturer who
had called upon him to see it at work, after expressing his admiration
at the ingenuity displayed in it, remarked, that wonderful as was Dr.
Cartwright's skill, there was one thing that would effectually baffle
him, and that was, the weaving of patterns in checks, or, in other
words, the combining in the same web a pattern or fancy figure with
the crossing colours which constitute the check. The doctor made no
reply to this at the time; but some weeks afterwards, on receiving a
second visit from the same person, he showed him a piece of muslin, of
the description mentioned, beautifully executed by machinery, which so
astonished the man, that he roundly declared his conviction that some
more than human agency must have been called in on the occasion.[11]
Dr. Cartwright being precluded by his clerical character from entering
himself into the manufacture of his machines, a weaving factory was
erected at Doncaster, by some friends, with his licence, but it
was unsuccessful; and another establishment, built at Manchester,
containing 500 looms, was destroyed by an exasperated mob in 1790.
Cartwright, however, still continued his inventions, and shortly
afterwards contrived a wool-combing machine, which met with even
fiercer opposition from the working-classes, who went the length of
petitioning parliament to suppress all such obnoxious machines. Their
great utility, however, caused them by degrees to be generally adopted;
and at the time of Cartwright's death, steam-looms had increased so
rapidly, that they were performing the work of 200,000 men.
Notwithstanding the great advantages which the cotton and wool
manufacturers reaped from these inventions, their author had as yet
obtained no emolument from them, but, on the contrary, had incurred a
heavy loss. In consideration of this, and on the petition of several
influential cotton-spinners, Parliament in 1810 made the doctor a
grant of 10,000_l._--a sum which, although munificent as a present,
hardly covered what he had expended in his experiments. Having received
the sum awarded by Parliament, and being now sixty-six years of age,
Dr. Cartwright was desirous of passing the remainder of his life in
retirement and tranquillity, and for this purpose purchased a small
farm at Hollenden, in Kent. At this place he spent the remainder of his
life, occupied in various scientific and mechanical experiments.
Dr. Cartwright was the author of many other inventions in the arts and
agriculture, for some of which he received premiums from the Board
of Agriculture and Society of Arts. He also contrived an ingenious
modification of the steam-engine, in which he made use of _surface
condensation_, and metallic spring packing for the piston.
Till within a few days of his death, Dr. Cartwright retained full
possession of his mental faculties, and attained, at the time of his
decease in 1823, the age of eighty-one. His remains were interred in
the church at Battle, in Sussex. _Memoir of Dr. Edmund Cartwright._
London, 1843.--_Stuart's Anecdotes of the Steam-Engine._ London, 1829.
THE HON. HENRY CAVENDISH, F.R.S.
Born October 10, 1731. Died February 24, 1810.
Henry Cavendish, the third in order of time among the four great
English pneumatic chemists of the eighteenth century,[12] was the
younger son of Lord Charles Cavendish, whose father was the second
Duke of Devonshire. His family trace back their descent in unbroken
and unquestionable links to Sir John Cavendish, Lord Chief Justice
during the reign of Edward III. The great majority of the distinguished
chemists of Great Britain have sprung from the middle and lower
ranks of the people, but in this respect Henry Cavendish presents
a remarkable exception. He was moreover immensely wealthy, so much
so, that it has been epigrammatically remarked of him, "That he was
the richest of all wise men, and probably, too, the wisest of all
rich men;" yet no one could well be more indifferent than he, to the
external advantages which are conferred by birth and fortune. Few
particulars are known of his early life. He was born at Nice, whither
his mother, who died when he was two years old, had gone for the sake
of her health.
In 1742 Cavendish became a pupil at Dr. Newcome's school at Hackney,
continuing his studies there until he had reached his seventeenth year,
when he went to Cambridge, where he matriculated in the first rank on
the 18th of December, 1749. He remained at this university until 1753,
but did not graduate.
After leaving Cambridge, the personal history of Cavendish becomes a
blank for the next ten years. He joined the Royal Society in 1760, but
did not contribute anything to its 'Transactions' until the year 1766,
when he published his paper 'On Factitious Airs,' which contains the
first distinct exposition of the properties of hydrogen, and the first
full account of those of carbonic acid; and a paper published by him in
the following year may be considered as a still further extension of
his research into the properties of this acid.
For some considerable time after this, Cavendish appears to have
laid aside Chemistry for other departments of physics. In 1771 he
published an elaborate paper on the theory of the principal phenomena
of electricity; and in 1776 appeared the curious and interesting
account of his attempts to imitate the effects of the torpedo, by an
apparatus constructed in imitation of the living fish, and placed in
connection with a frictional electrical machine and a Leyden battery.
In this imitation he succeeded so well, that all doubts were removed
as to the identity of the torpedinal benumbing power with common
electricity. In 1776 Cavendish was selected by the Royal Society,
in whose 'Transactions' all his previous papers had been published,
to describe the various meteorological instruments which were made
use of in their apartments; and the succeeding year to this marks
the period when he commenced his most important chemical researches,
entitled 'Experiments on Air,' which were carried on with frequent and
sometimes long interruptions until 1788, no part of them, however,
having been published before the year 1783. They led to the discovery
of the constant quantitative composition of the atmosphere, the
compound nature of water, and the composition of nitric acid. To solve
the important problems, whether the atmosphere is constant in its
composition, and if so, what is its composition? Cavendish experimented
in 1781 for some sixty successive days, making many hundred analyses of
air. The honour of the discovery of the compound nature of water, by
which perhaps his name has become most famous, is also claimed by James
Watt. Cavendish, however, seems at all events entitled to the honour
of having first supplied the data on which that discovery was founded,
whilst Watt appears to have supplied the conclusion.
Between the years 1783 and 1788, Cavendish published his papers on
'Heat,' and his 'Experiments on Air;' the former are three in number,
and relate chiefly to the phenomena of congelation, and embody some
of the results of experiments made as early as the year 1764. The
first of these papers refer to quicksilver, demonstrating the true
freezing-point of this metal to be 39° or 40° below zero, while the
second and third refer to the freezing of the mineral acids and of
alcohol.
His experiments on air, which led to the important results already
referred to, supplied materials for four papers, besides leading to the
observation of many phenomena which were never made public. With the
last of these papers published in 1788, Cavendish closed his chemical
researches, his remaining publications referring to meteorology and
astronomy.
In 1798 appeared the celebrated enquiry into the density of the earth,
communicated by Cavendish, in a paper to the Royal Society, in which
he determined, by means of an apparatus contrived by the Rev. John
Mitchell, the density of our globe to be 5·4,--or, in other words,
nearly five-and-a half times heavier than the same bulk of water would
be. The experiments made with this apparatus consisted in observing,
with many precautions, the movements of a long lever delicately
suspended by the centre, so as to hang horizontally, and furnished at
either extremity with small leaden balls. When two much larger and
heavier balls of the same metal were brought near the smaller ones,
the latter were attracted towards them with a certain force, the
measurement of which supplied one essential datum for the determination
of the mean density of the earth. No greater compliment to the accuracy
of the 'Cavendish Experiment' (as the researches taken as a whole are
generally called) can be afforded, than the slight difference which
appeared when the experiment was repeated at a later period by Francis
Baily, who, with extraordinary precautions to ensure a correct result,
and with all the improvements which forty fertile years had added to
mechanical contrivances, determined the density to be 5·6, or a little
more than five-and-a-half times that of water.
The last paper which Cavendish published, on an improvement in the
manner of dividing astronomical instruments, appeared in 1809,--a
year before his death. His published papers give, however, but an
imperfect notion of the great extent of ground over which he travelled
in the course of his investigations, and of the success with which
he explored it. He was an excellent mathematician, electrician,
astronomer, meteorologist, and geologist, and a chemist equally learned
and original. He lived retired from the world among his books and
instruments; he never meddled with the affairs of active life, but
passed his whole time in storing his mind with the knowledge imparted
by former inquirers, and in extending its bounds. His dress was of the
oldest fashion; his walk was quick and uneasy; he never appeared in
London unless lying back in the corner of his carriage; and he probably
uttered fewer words in the course of his life than any man who ever
lived to fourscore years. His private character has been thus described
by Dr. George Wilson, from whose comprehensive life of Cavendish the
present memoir has been chiefly taken:--
"Morally it was a blank, and can only be described by a series of
negations. He did not love, he did not hate, he did not hope, he did
not fear, he did not worship as others do. He separated himself from
his fellow men, and apparently from God. There was nothing earnest,
enthusiastic, heroic or chivalrous in his nature; and as little was
there anything mean, grovelling or ignoble. He was almost passionless.
An intellectual head thinking, a pair of wonderfully acute eyes
observing, and a pair of very skilful hands experimenting or recording,
are all that I recognize in his memorials. His brain seems to have been
but a calculating engine; his eyes inlets of vision, not fountains of
tears; his hands instruments of manipulation, which never trembled
with emotion, or were clasped together in adoration, thanksgiving
or despair; his heart only an anatomical organ necessary for the
circulation of the blood. A sense of isolation from his brethren made
him shrink from their society and avoid their presence; but he did so
as one conscious of an infirmity, not boasting of an excellence. He was
like a deaf mute, sitting apart from a circle whose looks and gestures
show that they are uttering and listening to music and eloquence, in
producing or welcoming which he can be no sharer. Wisely therefore he
dwelt apart. He was one of the unthanked benefactors of his race, who
was patiently teaching and serving mankind, whilst they were shrinking
from his coldness or mocking his peculiarities. He could not sing
for them a sweet song, or create a 'thing of beauty,' which would be
'a joy for ever,' or touch their hearts, or fire their spirits, or
deepen their reverence or their fervour. He was not a poet, a priest,
or a prophet, but only a cold clear intelligence, raying down pure
white light, which brightened everything on which it fell, but warmed
nothing--a star of at least the second, if not of the first magnitude
in the intellectual firmament."
As Cavendish had lived, so he died--alone. He died after a short
illness, probably the first as well as the last under which he ever
suffered. His habit of curious observation continued to the end; he was
desirous of marking the progress of disease and the gradual extinction
of the vital powers. With this view, that he might not be disturbed,
he desired to be left alone. His servant returning sooner than he
had wished was ordered again to leave the chamber of death, and when
he came back a second time he found his master had expired. Although
in many respects of a highly liberal character, so great was the
frugality of his ordinary mode of living in comparison to his income,
that at his death Cavendish left the enormous sum of 1,200,000_l._ to
be divided among his relations.--_Life of the Hon. Henry Cavendish,
by George Wilson, M.D., F.R.S.E._ London, 1851.--_Brougham's Lives of
Philosophers._ London and Glasgow, 1855.
WILLIAM CHAPMAN, M.R.I.A.
Born 1749. Died May 29, 1832.
William Chapman, Civil Engineer, was born at Whitby, in Yorkshire, of
a respectable and wealthy family, who had resided in that town for
several generations. He inherited the freedom of Newcastle-upon-Tyne
from his father, who, in common with all the chief people of Whitby,
was engaged in shipping, and was besides particularly distinguished
for his attainments in mathematics and other scientific pursuits.
William Chapman derived great advantage from his father's knowledge of
these subjects, contracting a strong taste for similar occupations.
After receiving a liberal education at different public schools, he was
put in command, at the early age of eighteen, of a merchant vessel,
in which he enjoyed the opportunity of visiting numerous harbours,
both in Great Britain and other countries. He continued thus occupied
for a period of three years, losing no opportunity of making himself
acquainted with the circumstances of the various harbours he was in
the habit of visiting, and he thus acquired that valuable practical
knowledge on the subject of these works for which he became afterwards
so highly distinguished.
After leaving the merchant service, Mr. Chapman was fortunate enough to
become acquainted with James Watt, with his partner Matthew Boulton,
and also with Mr. Wooller, Engineer to the Board of Ordnance. By
these eminent men he was strongly advised to become an engineer, and
follow as a profession that which he had already closely studied as an
amusement. Chapman accordingly accompanied Mr. Boulton into Ireland,
about the close of the year 1783, but although well introduced, was
unable to obtain any employment of consequence in that country, until
he had written a prize essay on the effects of the river Dodder on
the Harbour of Dublin. Shortly after this, he was appointed resident
engineer to the County of Kildare Canal, the works of which were
carried on under the surveillance of the Duke of Leinster, the county
members, and other leading men. In the execution of this undertaking,
Mr. Chapman was requested not to alter the direction of the roads
intersected by it, although one of them deviated from the right angle
across the canal upwards of 50 deg. To meet this difficulty, and
knowing that a bridge of the ordinary construction, with any obliquity,
could not possibly stand, Chapman invented, and put into practice, the
method of building oblique or skew bridges, which has since been so
generally adopted throughout the country, in railway, canal, and other
bridges. Before this period, (1787), whenever a road crossed the course
of a canal or river, requiring the construction of a bridge, it had
been usual to deviate the course, either of the road or the object it
crossed, so that the crossing should be at right angles; a practice
which occasioned a great waste of land and considerable expense as
well as awkward and dangerous bends in the roads thus treated. In some
few cases where the bridge was required to be of only a small opening,
no alteration in the direction was made, but a bridge built of an
oblique form, that is with abutments forming oblique angles with the
road passing over it, the courses of the arch being built in lines
parallel with the abutments, and the ends of the voussoirs bevelled
off to coincide with the direction of the road. Bridges built in this
manner consequently became highly dangerous when the span was great, or
the obliquity considerable. The value of Chapman's invention consists
in this, that he gave the means of building bridges on the skew
principle, in any required situation, without altering the direction of
the roads or wasting material, and at an expense little above that of
ordinary rectangular bridges. This he accomplished by the principle of
building the courses of voussoirs at right angles to the face of the
arch, meeting the abutments at oblique angles, being the very reverse
of the system previously practised.
During the progress of the Kildare Canal, Mr. Chapman, at the request
of the Duke of Leinster, became overseer, conjointly with him and the
Hon. Mr. Ponsonby Moore, for the building a bridge of five arches over
the Liffey, to replace the former one which had been carried away
by a flood. The bridge itself was a plain structure, but the means
employed in forming and securing the foundations attracted general
attention, and brought Mr. Chapman into still greater notice. From
this time the number and importance of his professional engagements
continued to increase, and he was engaged to survey and report upon
several projects for the improvement of the navigations of various
rivers, of which plans the most important was the navigation of the
river Barrow, from Athy downwards. During this period he was appointed
consulting engineer to the Grand Canal of Ireland, of which undertaking
Mr. Jessop was directing engineer; and under the joint superintendence
and surveys of these two gentlemen, the extension of the Grand Canal
from Robarts Town to Tullamore was laid out, as well as the Dock
between Dublin and Ringsend, and the canal of communication by the
line of the circular road. The projected canal from near Tullamore
passed through extensive bogs, some of which were thirty feet in depth,
and in consequence of its difficulties was laid out by Mr. Chapman
himself. The directors of the Grand canal had expended upwards of
100,000_l._ in a very short space of ground between Robarts Town and
Bathangar, from not being acquainted with the extent of the subsidence
of bogs under superincumbent weight, or when laid dry by drainage.
Mr. Chapman, therefore, availed himself of their dearly bought
experience, and adopted the following ingenious method of comparing
different kinds of bogs and their relative subsidence. He provided
himself with a cylindric implement of steel plate, sharp at the lower
edges, and containing exactly one hundredth part of a cubic foot, and
having divided the strata of the bogs into as many leading classes and
subdivisions as were necessary, he filled the cylinders with a specimen
of each, by twisting them round so as to cut the fibres of the bog. The
samples thus taken were carefully cut off at the level of the cylindric
guage, and their weight having been ascertained, they were left to
dry during the space of several months; and when in a firm state and
consequently greatly contracted, were again weighed, the result being
that the originally wettest bog was found to have lost 10-11ths of its
weight, and the firmest 2-3rds, the rest in due progression between.
It therefore became a simple process to ascertain pretty nearly the
extent of subsidence in any bog to be passed through, and of course to
lay out the line of the canal with such levels, that after subsidence,
its surface should be at the required depth below the surface of the
bog.