-----
Footnote 1:
Apuleius, Floridor, page 361.
Footnote 2:
Theophrast. περι λιδων.
Footnote 3:
Dr. Falconer, in a paper inserted in the “Memoirs of the Manchester
Society,” has endeavoured to prove by quotations from the writings of
antiquity, and by much ingenious reasoning, that the ancients were not
only acquainted with the electrical shock, but that it is probable
even the method of drawing down lightning from the clouds, was known
in very early times, and particularly to Numa Pompilius, the second
king of Rome; and that his successor Tullius Hostilius perished, by
his unskilful management of so dangerous a process.
Those who wish to pursue this subject, we refer to the above mentioned
paper in 3 vol. Memoirs of the Literary and Philosophical Society of
Manchester, page 378.
The same opinion is ingeniously defended, in a work of M. Dutens,
entitled, “Origine des Decouvertes atribuees aux Modernes.” Some
curious quotations from the ancients, on electricity, are likewise
contained in the Gentleman’s Magazine for July 1785, page 522.
“To these may be added a curious passage in Signor Boccalini’s
advertisement from Parnassus (century 1. chap. 46,) published more
than a hundred years before the date of Franklin’s discovery, and in
which the identity of the electric fluid and lightning is said to be
revealed.” Miller’s Retrospect, 1 vol. page 24.
But after attentively considering all these discoveries, we cannot
help acceding to the opinion of the learned President Gouget, a man
who had most thoroughly investigated the origin of science among the
ancients, and we are fully persuaded that what he says of several
other subjects is precisely the truth in regard to electricity.—“All
(says he) which we read on this subject in the writings of the
ancients, ought to be regarded as mere ideas advanced at random,
without knowledge, without principles, and without any kind of
foundation. If some of the ancients, for example, have said, that the
earth was a spheroid, flattened at the poles; that it revolved round
the sun; that the comets were planets, whose periodical revolutions
were completed in a certain number of ages; that the moon might be
habitable; that that planet was the occasional cause of the flux and
reflux of the sea, &c.; we ought not to regard these propositions in
their mouth, as the effect and the result of the knowledge which these
philosophers had acquired. On the contrary, we ought to place them on
the footing of those hypotheses which an uncertain and ill-regulated
imagination daily produces. I say so, because none of the ancient
philosophers have been able to give reasons for what they delivered;
which we may be easily convinced of, by reading the manner in which
the writers of antiquity relate the opinions of their learned. There
we see, that the ancients had no reasons preponderating to adopt one
system rather than another; neither were they ever able to give any of
them the slightest demonstration. For the rest, I do not pretend to
make this a matter of reproach to the ancients. They were destitute of
all helps proper to acquire these branches of knowledge. If,
nevertheless, they have sometimes hit upon the truth, we ought to
attribute it to pure chance; and be sensible, that, as they wavered in
uncertainty, and ran through all possible combinations, it is not
astonishing that they should hit upon the true one, because the number
of these sorts of combinations is not infinite. In this respect
consists the characteristical difference between the astronomical
learning of the ancients and that of the moderns. What at this time we
affirm of the figure of the earth, of the system of the heavens, of
the cause of the flux and reflux of the sea, &c. is not the effect of
chance and imagination; it is the result of much observation,
experience, and reflection, and every astronomer is able to support by
reasons the system which he has thought fit to embrace.”
_Origin of Laws, Arts, and Sciences_, Vol. III, Book III, Chap. II,
Article IV.
Footnote 4:
Bayle in Vita Aristot.
Footnote 5:
Gilbert, De Magnete. Lib. 2, Cap. 2.
Footnote 6:
Philos. Trans. abridged, Vol. 7, page 18.
Footnote 7:
The author of the article Electricity in the Encyclopædia, ascribes
the merit of this discovery (if any merit can arise from a discovery
made by accident) to Mr. Van Kleist, dean of the cathedral of Camin.
On what authority he does this, we are unable to state. The following
(he says) is the account of it, which the dean, on the 4th of November
1745, sent to Dr. Leiberkulm at Berlin, “When a nail, or a piece of
thick brass wire, &c. is put into a small apothecary’s phial, and
electrified, remarkable effects follow: but the phial must be very
dry, or warm. I commonly rub it over before-hand with a finger, on
which I put some pounded chalk.—If a little mercury or a few drops of
spirit of wine are put into it, the experiment succeeds the better. As
soon as this phial and nail are removed from the electrifying glass,
or the prime-conductor to which it hath been exposed is taken away, it
throws out a pencil of flame so long, that with this burning machine
in my hand, I have taken above sixty steps in walking about my room.
When it is electrified strongly, I can take it into another room, and
there fire spirits of wine with it. If while it is electrifying I put
my finger, or a piece of gold which I hold in my hand, to the nail, I
receive a shock which stuns my arms and shoulders.”
“A tin tube, or a man, placed upon electrics, is electrified much
stronger by this means, than in the common way.—When I present this
phial and nail to a tin tube, which I have, fifteen inches long,
nothing but experience can make a person believe how strongly it is
electrified. Two thin glasses have been broken by the shock of it.”
Footnote 8:
Such is the statement usually given. It may perhaps deserve
consideration whether _the cause_ of this luminous spark or stream,
should not, strictly speaking, be considered as the true electricity.
Footnote 9:
Tourmaline is a species of silicious earth. Its colour is generally a
blackish brown, though the tourmaline of Brazil is blue, green, red,
or yellow. It is a compound substance, consisting of argill, silex,
calcareous earth, and iron in different proportions; but argill and
silex are always the chief ingredients. It is found in Ceylon, Brazil,
and Tyrol; and it is also found in large quantities in the
neighbourhood of Philadelphia, attached to masses of quartz.
Footnote 10:
It is very remarkable that the focus of a burning glass is not a
conductor of electricity.
Footnote 11:
We do not wish to be understood that _two different_ fluids may be
produced, but merely, that the prime conductor may be electrified
_positively_ or _negatively_.
Footnote 12:
For the proper cement, see appendix NO. I.
Footnote 13:
See appendix NO. II.
Footnote 14:
See appendix NO. III.
Footnote 15:
This consists of two small balls of cork or pith, fastened to the ends
of a thread or piece of silk. When it is to be used the thread or silk
must be held by the middle so that the balls may hang close to one
another.
Footnote 16:
Mr. Richman, professor at Petersburg, was killed on the 6th of August,
1753, by the lightning which he had drawn into his room, for the
purpose of making experiments. The circumstances of this interesting
and instructive occurrence were the following.
He had provided himself with an instrument for measuring the quantity
of electricity communicated to his apparatus, and as he stood with his
head inclined towards it, Mr. Solokow, an engraver, who was near him,
observed a globe of blue fire as large as his fist, jump from the
instrument, which was about a foot distant, to Mr. Richman’s head. The
professor was instantly dead, and Mr. Solokow much hurt. The latter
however could not give any particular account of the way in which he
was affected; for at the time when he was struck, there arose a sort
of steam or vapour, which entirely benumbed him, and made him sink to
the floor; he did not even remember to have heard the clap of thunder,
which was very loud.—The globe of fire was attended with an explosion
like that of a pistol; the instrument for measuring the electricity
(called by the professor the electrical gnomon) was broken to pieces,
and the fragments scattered about the room. Upon examining the effects
of the lightning in the chamber, the door-case was split half through,
and the door torn off the hinges, and thrown into the room.
They opened a vein in the body twice, but no blood followed; after
which they endeavoured to recover life by violent friction, but in
vain: upon turning the corpse with the face downwards, during the
friction, a quantity of blood ran from the mouth. There appeared a red
spot upon the forehead, from which spirted a few drops of blood from
the pores, without wounding the skin; the shoe of the left foot was
torn open, and upon uncovering the part, a blue mark was found; from
which it was concluded, that the electric matter having entered at the
head, made its way out again at the foot. Upon the body, particularly
on the left side, were several red and blue spots, resembling leather
shrunk by being burnt. Many more also became visible over the whole
body, and especially over the back.—That on the forehead changed to a
brownish red, but the hair of the head was not singed.
In the place where the shoe was unripped, the stocking was entire, as
was the coat every where; the waistcoat being only singed at the fore
flap where it joined the hinder; but on Mr. Solokow’s coat there
appeared long narrow stripes, as if the nap had been burnt off by red
hot wires. These could not be accounted for.
Footnote 17:
This looks something like a contradiction: but we suppose Mr. Cavallo
intended to say, that though the coat of paint does not prevent the
shock from passing down the mast, it prevented the mast from being
injured by the shock.
Footnote 18:
For proper cement, see Appendix to electricity, No. I.
Footnote 19:
The pile and trough, are both sometimes denominated _Batteries_.
Footnote 20:
Volta by the aid of his condenser of electricity, discovered that the
two extremities of his pile were in opposite states; the zinc end was
always plus or positive, and the silver end, minus or negative.
Footnote 21:
This sub-acid taste, is rendered much more distinct by an instrument
invented by Professor Robinson, and described by him in a letter to
Dr. Fowler, dated 28th May, 1793. It is made by placing alternately a
number of small circular pieces of zinc, with as many pieces of silver
of the same size, in the form of a _rouleau_. It is to be used by
placing it laterally upon the tongue.
Footnote 22:
With regard to the similarity between the taste of Galvanism and that
of electricity, Dr. Fowler observes that he found considerable
difference between them—. “Both (says he) are sub-acid, but as unlike
each other, as the taste of vinegar is to that of diluted vitriolic
acid.”
This sensation, produced upon the tongue by Galvanism, is most
distinct when the tongue is of its usual temperature, and the metals
of the same temperature with it. When either the tongue, the metals,
or both, are heated or cooled, as far as can be borne without
inconvenience, scarcely any taste is produced.
Footnote 23:
This is the explanation given by Mr. Wilkinson, but we think it
probable that this effect is altogether chemical.
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TRANSCRIBER’S NOTES
● Typos fixed; non-standard spelling and dialect retained.
● Used numbers for footnotes, placing them all at the end of the last
chapter.
● Enclosed italics font in _underscores_.