Chapter XXVI: Part II: pp. 254–256, 279, for some of his other correspondence (3)

This electroscope, says Wilkinson, possesses great sensibility, and through the movable coatings introduced by Mr. Pepys, very small portions of electricity are discernible. Another very excellent electroscope is formed with either extremely fine silver thread, prepared after the manner of Mr. Read, or with the minutest thread found in a bundle of very fine flax, having a little isinglass glue applied gently over it with the finger and thumb.

Of the numerous observations made by Bennet, the following interesting extract relative to the phenomenon of evaporation is taken from the _Philosophical Transactions_ for the year 1787. “If a metal cup with a red hot coal in it be placed upon the cap of a gold leaf electroscope, a spoonful of water thrown in electrifies the cup resinously; and if a bent wire be placed in the cup with a piece of paper fastened to it to increase its surface, the vitreous electricity of the ascending column of vapour may be seen by introducing the paper into it. The experiments on the evaporation of water may be tried with more ease and certainty of success by heating the small end of a tobacco pipe and pouring water into the head, which, running down to the heated part, is suddenly expanded, and will show its electricity when projected upon the cap of the electrometer more sensibly than any other way that I have tried. If the pipe be fixed in a cloven stick and placed in the cup of one electrometer while the steam is projected upon another, it produces both electricities at once.”

Some of Mr. Bennet’s experiments with the electroscope on the electricity of sifted powders, upon the electricity of the atmosphere, etc., are recorded at pp. 564 and 566 of the “Britannica,” Vol. VIII, and at p. 56 of “Library of Useful Knowledge.”

Mr. Bennet also invented the _electrical doubler_, designed to increase small quantities of electricity by continually doubling them until visible in sparks or until the common electrometer indicates their presence and quality (_Phil. Trans._ for 1787, p. 288). It consists of three plates of brass, illustrated and explained at Fig. 9, p. 20, Vol. I of Prescott’s “Electricity and the Electric Telegraph,” 1885 edition, wherein it is stated that in forty seconds the electricity can thus, by continual duplication, be augmented five hundred thousand times. (See, for doublers, C. B. Désormes and J. N. P. Hachette, in _Annales de Chimie_, Vol. XLIX for 1804; J. Read (_Phil. Trans._ for 1794, p. 266); Sir Francis Ronalds (Edin. “Phil. Journal,” Vol. IX. pp. 323–325).)

At p. 105 of his “Rudim. Magnetism,” Snow Harris mentions the fact that, in some of his experiments, Mr. Bennet employed a magnetic needle suspended by filaments of a spider’s web as a magnetometer. In this connection, it may be said that, in the _Philosophical Transactions_ for 1792, the assertion is made that a fine, and weakly magnetic steel wire suspended from a spider’s thread of three inches in length will admit of being twisted around eighteen thousand times and yet continue to point accurately in the meridian, so little is the thread sensible of torsion (Young’s “Course of Lectures,” 1807, Vol. II. p. 445). The use of the spider’s line had, during the year 1775, been recommended as a substitute for wires by Gregorio Fontana, who, it is said, obtained threads as fine as the eight-thousandth part of a line. In a lecture delivered at Boston, Mass., during the year 1884, Prof. Wood alluded to spiders’ threads estimated to be one two-millionths of a hair in thickness.

REFERENCES.--Bennet, “New Experiments on Electricity,” etc.,
Derby, 1789, and “A New Suspension of the Magnetic Needle,”
etc., London, 1792; Introduction to “Electrical Researches,” by
Lord Henry Cavendish; _Sc. Am. Supplement_, No. 647, pp. 10,
327; Noad, “Manual,” p. 27; Cavallo, “Nat. Phil.,” 1825, Vol.
II. pp. 199, 216; _Phil. Trans._, Vol. LXXVII. pp. 26–31, 32–34,
288–296; also the abridgments by Hutton, Vol. XVI. pp. 173,
176, 282 and Vol. XVII. p. 142; _Sc. American_, Vol. LI. p. 19;
_Annales de Chimie_, Vol. XLIX. p. 45; Ezekiel Walker, _Phil.
Mag._ for 1813, Vol. XLI. p. 415 and Vol. XLII. pp. 161, 215,
217, 371, 476, 485; also Vol. XLIII. p. 364.

=A.D. 1788.=--Barthélémy (Jean Jacques), who, after completing his studies in a French seminary of Jesuits, succeeded Gros de Boze as keeper of the king’s cabinet of medals, publishes in four volumes, at Paris, the first edition of his “Voyage du Jeune Anacharsis.” In this well-known work, begun by him in 1757, and translated into English under the title “Travels of Anacharsis the Younger in Greece,” Barthélémy alludes to the possibility of telegraphing by means of clocks (_pendules_, not _horloges_), having hands similarly magnetized in conjunction with artificial magnets. These were “presumed to be so far improved that they could convey their directive power to a distance, thus, by the sympathetic movements of the hands or needles in connection with a dial alphabet, communications between distant friends could be carried on.”

Writing to Mme. du Deffand in 1772, he observes:

“It is said that with two timepieces the hands of which are magnetic, it is enough to move one of these hands to make the other take the same direction, so that by causing one to strike twelve the other will strike the same hour. Let us suppose that artificial magnets were improved to the point that their virtue could communicate itself from here to Paris; you have one of these timepieces, we another of them; instead of hours we find the letters of the alphabet on the dial. Every day at a certain hour we turn the hand, and M. Wiard [Mme. du Deffand’s secretary] puts together the letters and reads.... This idea pleases me immensely. It would soon be corrupted by applying it to spying in armies and in politics, but it would be very agreeable in commerce and in friendship.”

REFERENCES.--“Correspondance inédite de Mad. Du Deffand,” Vol.
II. p. 99; letter of J. MacGregor in _Journal Society of Arts_,
May 20, 1859, pp. 472, 473.

=A.D. 1789.=--Adriaan Paets Van Troostwÿk and Jean Rodolphe Deimann, Dutch chemists, associated for the purpose of scientific research, complete the experiments of Lord Cavendish and announce, in the _Journal de Physique_, their discovery of the decomposition of water through the electric spark, which latter is conveyed by means of very fine gold wires. As is now well known, water is by this means resolved into its two elements of oxygen and hydrogen, both of which assume their gaseous form.

The electric machine they employed was a very powerful double-plate one, of the Teylerian mode of construction, causing the Leyden jar to discharge itself twenty-five times in fifteen revolutions.

REFERENCES.--“Mém. de la Soc. de Phys. Exp. Rotterdam,” Tome
VIII; _Journal de Physique_, Vol. XXXIII; Noad, “Manual,” p.
161; “Encyl. Brit.,” Vol. VIII, 1855, pp. 530, 565; “Biog.
Universelle,” Vol. X. p. 282; De La Rive, “Electricity,” Vol.
II. p. 443; Wm. Henry, “Elements of Experimental Chemistry,”
London, 1823, Vol. I. pp. 251, 252; Delaunay’s “Manuel,” etc.,
1809, pp. 180–183; “Verhandl. van het Genootsch te Rotterdam”
(“Mém. de la Soc. de Phys. Exp. de Rotterdam”) Vol. VIII;
Poggendorff, Vol. I. p. 1555; Dove, p. 243; G. Carradori
(Brugnatelli’s _Annali di chimica_, Vol. I. p. 1); John
Cuthbertson, “Beschreibung einer Elekt. ...” Leipzig, 1790.

=A.D. 1790.=--Reveroni--Saint-Cyr (Jacques Antoine, Baron de), French Colonel and author, best known by his very interesting work, “Mécanismes de la Guerre,” proposes an electric telegraph for the purpose of announcing the drawings of lottery numbers; no satisfactory information as to its construction, however, appears obtainable.

REFERENCES.--Fahie, “History,” etc., London, 1884, p. 96;
Etenaud, “La Télégraphie Electrique,” 1872, Vol. I. p. 27; _Sc.
Am. Supp._, No. 384, pp. 6, 126.

=A.D. 1790.=--Mr. Downie, master of his Majesty’s ship “Glory,” makes a report on local attraction wherein he observes “that in all latitudes, at any distance from the magnetic equator, the upper ends of iron bolts acquire an opposite polarity to that of the latitude,” an observation, Harris remarks, which accords with Marcel’s experiment (at A.D. 1702).

“I am convinced,” says Mr. Downie, “that the quantity and vicinity of iron, in most ships, has an effect in attracting the needle; for it is found by experience that the needle will not always point in the same direction when placed in different parts of a ship; also, it is very easily found that two ships, steering the same course by their respective compasses, will not go exactly parallel to each other; yet when their compasses are on board the same ship they will agree exactly.”

REFERENCES.--William Walker, “The Magnetism of Ships,” London,
1853, p. 20; J. Farrar, “Elements,” p. 376; Harris, “Rudim.
Magn.,” 1852, Part III. p. 161.

=A.D. 1790.=--Tralles (Johann Georg), a German scientist, is the first to make known the negative electricity of cascades. This he communicates through his “Uber d. Elektricität d. Staubbachs,” published at Leipzig.

In the Report on Atmospheric Electricity of Francis J. F. Duprez, translated from the Memoirs of the Royal Academy of Brussels by Dr. L. D. Gale, we read that one day while in the Alps, opposite the cascade of Staubbach, near Lauterbrunnen, Tralles “presented his atmospheric electrometer, not armed with the metallic wire, to the fine spray which resulted from the dispersion of the water. He immediately obtained very distinct signs of negative electricity. The same effect was exhibited at the cascade of Reichenbach. Volta, a short time after, verified the correctness of this observation, not only above the great cascades, but also wherever a fall of water existed, however small, provided the intervention of the wind caused the dispersion of the drops. The electricity always appeared to him, as it did to Tralles, negative. Schübler repeated the same experiments in his journey to the Alps in 1813. He observed farther, that this negative electricity was very strong, since it became perceptible at a distance of 300 feet from the cascade of Reichenbach; and at a distance of 100 feet his electrometer indicated 400 and even 500 degrees.... Tralles attributed it at first to the friction of the minute drops of water against the air; but soon after he thought, with Volta, that the cause was to be found in the evaporation which the same minute drops experience in falling....”

The Italian physicist, Giuseppe Belli, who published at Milan, during 1836, “Sulla Elettricità negativa delle cascate,” entertains an opinion contrary to that advanced by M. Becquerel, and believes “that the electrical phenomenon of the water of cascades is owing to the development of electricity by the induction which the positive electricity of the atmosphere exercises on the water. The water, he says, is by induction in the negative state, when the atmosphere is, as it is ordinarily, charged with positive electricity. At the moment when this water divides into thousands of minute drops, it cannot fail to carry the electricity with which the electrical induction of the atmosphere has impregnated it to all bodies which it meets.”

REFERENCES.--“Œuvres de Volta,” Vol. II. p. 239; Franz Samuel
Wilde, “Expériences sur l’électricité des cascades” (“Mémoires
de Lausanne,” Vol. III, “Histoire,” p. 13, 1790); “Bibliographie
Universelle,” N. S., 1836, Vol. VI. p. 148; Houzeau et
Lancaster, “Bibl. Générale,” Vol. II. p. 265; “Biblio. Ital.,”
LXXXIII. p. 32; Schweigger, _Journal f. Chemie u. Physik_, Vol.
IX. p. 358; Tralles, “Beyträge zur Lehre von der Electricität”;
L. W. Gilbert’s _Annalen der Physik und Chemie_, Vol. XXVIII
for 1808; F. A. C. Gren’s _Journal der Physik_, Vol. I. for
1790; Humboldt, “Cosmos,” London, 1849, Vol. I. p. 344, and the
reference to Gay-Lussac in _Ann. de chimie et de physique_, Vol.
VIII. p. 167.

=A.D. 1790.=--Eandi (Giuseppe Antonio Francesco Geronimo), an able physicist, native of Saluces (1735–1799), reads, May 10, before the Academy of Sciences of Turin, a Memoir upon Electricity _in vacuo_ which is printed in the Collections of that Institution. He studied for the priesthood and entered the Normal College of Turin, where he followed protracted courses of literature under Bartoli and of natural philosophy under Beccaria, becoming the assistant of the latter, whom he finally replaced from 1776 to 1781. He afterward became Professor of Natural Philosophy at the College of Fine Arts, where he gave particular attention to electrical studies, and published several papers on that science, as well as upon natural philosophy generally.

He bequeathed all his possessions to his nephew Vassalli, upon condition of the latter’s taking the name of Eandi.

Besides the above, he wrote: “Memorie istorische,” etc., or “Historical Memoir upon the Studies of Father Beccaria,” Turin, 1783, which is dedicated to Count Balbi and gives the new theories of electricity, also an “Essay upon the Errors of Several Physicists in Regard to Electricity,” Turin, 1788.

REFERENCES.--“Notice sur la vie ... d’ Eandi par
Vassalli-Eandi,” Turin, 1804; “Biographie Générale,” Vol. XV.
p. 589; Larousse, “Dict. Universel,” Vol. VII. p. 5; the Turin
Academy Memoirs for the years 1802–1804; Eandi e Vassalli-Eandi,
“Physicæ Experimentalis,” etc., Turin, 1793–1794.

=A.D. 1790.=--Vassalli-Eandi (Antonio Maria), Italian savant (1761–1825), nephew of G. A. F. G. Eandi, who was, like his uncle, a pupil of Beccaria, publishes his views concerning the electricity of bodies and regarding other investigations, as well as a report upon experiments relative to the electricity of water and of ice, which appear respectively in L. V. Brugnatelli’s _Annali di Chimica_, Vol. I. p. 53, in the “Bibl. Fis. d’Europa,” Vol. XVII. p. 144, and in the third volume of “Mem. della Soc. Italiana.”

He was one of the most prolific of Italian writers, his more important essays, which number 160, being written in Italian, Latin and French, and covering almost every leading branch of physical science. One of his biographers tells us, _Il a embrassé, pour ainsi dire, l’ensemble des connaissances humaines_, and that he is one of whom his country may justly be proud.

In his investigations concerning aerolites, which appeared in 1786 (“Memoria ... sopra ... bolidi in generale”), he explains the movements of those bodies much more satisfactorily than had previously been done by any scientist. Essays published by him during the same year, as well as in 1789 and 1791, treat of the effect of electricity upon vegetables; then follow his papers relative to Bertholon’s “Electricité des Météores,” to Haüy’s theories and to the meteorological observations of Senebier, De Saussure, Toaldo and Monge, up to 1792, when Vassalli was made Professor of Natural Philosophy at the Turin University. He had also in the meantime carefully looked into the scientific knowledge possessed by the ancients, and was led to believe, as shown in his “Conghietture sopra l’arte,” etc., that they had the means of attracting and directing thunder and lightning. The latter fact has been alluded to in this “Bibliographical History,” under the B.C. 600 entry. (See J. Bouillet, “De l’état des connaissances,” etc., Saint Etienne, 1862.)

He was after this made perpetual secretary of the Royal Academy of Sciences of Turin, then became Director of the Museum of Natural History, as well as of the Observatory situated in the last-named city, which position he held at the time of his death.

His other essays treat more particularly of animal electricity, the electricity of fishes, the effects of electricity upon recently decapitated bodies, the application of electricity and of galvanism to medicine, and cover very extended observations on meteorology. He was the editor of both the “Memoirs of the Academy of Sciences of Turin, from 1792 to 1809,” and of the “Annals of the Turin Observatory, from 1809 to 1818” (Larousse, “Dictionnaire Universel,” Vol. XV. p. 801); was likewise editor of the “Bibliothèque Italienne,” in conjunction with Giulio Gioberti and Francesco Rossi, and is said to have devised an electrometer superior to that of Volta.

REFERENCES.--Vassalli-Eandi, Giulio (or Julio) e Rossi, “Rapport
présenté,” etc., Turin, 1802, or “Transunto del Rapporto,” etc.,
Milano, 1803 (“Opusc. Scelti,” Vol. XXII. p. 51), translated
into English, London, 1803 (_Phil. Mag._, Vol. XV. p. 38); also
Vassalli-Eandi, F. Rossi et V. Michelotti, “Précis de nouvelles
expériences galvaniques,” Turin, 1809 (“Mém. de Turin,” Années,
1805–1808, p. 160). See likewise, S. Berrutti, “Elogio,” etc.,
1839; “Saggio sulla vita ... Vassalli-Eandi,” Torino, 1825;
“Notizie biografiche ... Vassalli Eandi” (“Mem. di Torino,”
Vol. XXX. p. 19); “Elogio, scritto dal Berrutti” (“Mem. of the
Ital. Soc.,” Vol. XXII. p. liv); _Phil. Mag._, Vol. XV. p.
319; _Journal de Physique_, An. VII. p. 336 and Vols. XLIX,
L; “Ital. Soc. Mem.,” Vols. VIII. p. 516; X. p. 802; XIII.
p. 85; XVII. p. 230; XIX. p. 347; “Mémoires de Turin,” Vols.
X-XIII; “Mem. dell’ Acad. di Torino,” Vols. VI, X, XXII, XXIV,
XXVI, XXVII, XXIX; “Mem. della Soc. Agrar. di Torino,” Vol.
I; “Opuscoli Scelti,” Vols. XIX. pp. 215, etc.; XXII. p. 76;
“Nuova Scelta d’Opuscoli,” Vol. I. p. 167; “Opuscoli Scelti
di Milano,” quarto, Vol. XIV; “Mem. Soc. Ital.,” Vols. IV.
p. 263; X. p. 733; “Biblioteca Oltramontana”; Brugnatelli’s
_Annali di Chimica_; “Giornale Scientifico ... di Torino,”
Vols. I, III; “Giornale Fis. Med.,” Vol. II. p. 110; “Biblioteca
Italiana”--“Bibliothèque Italienne,” Vols. I. p. 128; II. p. 25;
“Recueil périodique ... de Sédillot,” Vol. II. p. 266.

=A.D. 1790–1800.=--Morozzo--Morotius--(Carlo Luigi, Comte de), Italian savant, who studied mathematics under Lagrange, and was President of the Turin Academy of Sciences, publishes numerous scientific memoirs in French through the reports of the last-named institution, in one of which he is said to have described an experiment suggesting the electro-magnet.

REFERENCES.--Biography in Larousse, “Dictionnaire Universel,”
Tome XI. p. 577, and in the “Biographie Générale,” Tome XXXVI.
p. 643.

=A.D. 1791.=--Leslie (Sir John), an able English scientist (April 1766–Nov. 1832), who, upon the death of Prof. John Playfair, was called to the Chair of Natural Philosophy in the University of Edinburgh, writes a very interesting paper entitled “Observations on Electric Theories,” which is read the following year at the meeting of the Royal Society of Edinburgh, and is published at the latter place during 1824.

According to Carnevale Antonio Arella, “Storia dell’ Elettricità,” Alessandria, 1839, Vol. I. p. 130, Sir John Leslie is the author of quite an interesting treatise on the inefficacy of lightning conductors, and the “English Cyclopædia” (Biography), Vol. III. p. 866, gives a list of many of the numerous contributions he made to the leading publications of his day, more particularly in the “Edinburgh Philos. Transactions,” the “Encyclopædia Britannica,” the “Edinburgh Review,” and “Nicholson’s Philos. Journal.” The reviewer adds, what will surprise many readers, that, although some papers by Sir John Leslie treating of physical subjects were also read before the Royal Society of London, none were ever printed in their “Philos. Transactions.”

Professor John Playfair above alluded to (1748–1819), became, during 1785, Joint Professor of Mathematics with Dr. Adam Ferguson in the University of Edinburgh and, in 1805, exchanged this for the Professorship of Natural Philosophy in the same university.

REFERENCES.--Macvey Napier, “Memoir of Sir John Leslie,” 1838,
which appeared in seventh edition of “Encycl. Britan.,” Vol.
XIII; “Engl. Cycl.” (Biography); Rose, “New Gen. Biogr.”; Hœfer,
“Nouv. Biogr. Gen.,” Paris, 1862, Vol. XXX. pp. 949–952 (giving
full account of his works); “Encycl. Britan.,” ninth edition,
Edinburgh, 1882, Vol. XIV. pp. 476–477; Sidney Lee, “Dict. Nat.
Biogr.,” Vol. XXXIII. pp. 105–107 and Vol. XLVIII. pp. 413–414;
Pierre Larousse, “Grand Dict. Univ.,” Vol. X. pp. 406–407;
“Caledonian Mercury,” article of Prof. Napier summarized in the
“Gentleman’s Magazine” for 1833, Vol. I. pp. 85–86. Consult also
A.D. 1751 at Adanson; “Dove,” p. 256; _Philosophical Magazine_,
Vols. XL and XLII.

=A.D. 1791.=--At p. 353, Chap. III of the first volume of Gmelin’s “Handbook of Chemistry,” it is stated that during 1791 James Keir (Kier) first showed, by immersing iron in a solution of nitrate of silver or fuming nitric acid, that many metals can be made to pass from their ordinary _active_ state into a _passive_ or electro-negative state and lose either wholly or in part their tendency to decompose acids and metallic oxides.

At pp. 167–170, Sixth Memoir, of Wm. Sturgeon’s “Scientific Researches” (Bury, 1850), treating of the application of electro-chemistry to the dissolution of simple metals in fluids, reference is made to the long line of investigations carried on by both Bergman and Keir, the last named having demonstrated that iron “acquires that _altered_ state by the action of nitric acid which Sir John Herschel met with in his experiments, and has called _prepared_ state, and that Schönbein and others call the _peculiar_ or the _inactive_ state” (Noad’s “Manual of Electricity,” London, 1859, p. 534). The iron which is active in nitric acid was called by Keir “fresh iron,” while that which became inactive he designated as “altered iron” (Sturgeon’s “Annals of Electricity,” Vol. V. p. 439).

Some remarkable phenomena in the display of which but one individual piece of metal is used, as first shown by Keir, remain, Sturgeon says, “without even an attempt at explanation by any of the philosophers under whose notice they have appeared.” Sir John Herschel pronounces them as of an “extraordinary character”; Prof. Andrews, after giving some very satisfactory explanations of several phenomena, acknowledges that he “can offer no explanation of most of the particular facts which have been described,” and Professor Schönbein “has not made public any conclusive explanation of them whatever” (_Phil. Mag._ for October 1837, p. 333, and for April 1838, p. 311).

This same James Keir, called by Watt “a mighty chemist” (1735–1820), has strangely by some been confounded with Robert Kerr, also a Scotchman, who was an able scientific writer and lived at about the same period (1755–1813). Kerr made valuable translations from Lavoisier and Linnæus which, during 1805, won for him a fellowship in the Edinburgh Royal Society. (Consult Sidney Lee, “Dict. of Nat. Biogr.,” London, 1892, Vol. XXI. p. 64, also the references therein given; and the article “Faraday” in the “Encycl. Britan.,” ninth edition, Edinburgh, 1879, Vol. IX. p. 30.)

REFERENCES.--Mrs. Amelia Moillet, “Sketch of the Life of
James Keir,” 1859; Sidney Lee, “Dict. of Nat. Biog.,” London,
1892, Vol. XXX. pp. 313–314; _Annales de Chimie_ for October
1837; _Phil. Trans._ for 1790, p. 353, as well as Hutton’s
abridgment of the same, Vol. XVI. p. 694; Sturgeon’s “Annals of
Electricity,” Vol. V. p. 427; Gmelin’s Chemistry, pp. 367, 370.

=A.D. 1791.=--Shaw (George), English naturalist, who became a Fellow of the Royal Society during the year 1789, communicates to the latter body a paper on the _Scolopendra electrica_ and _Scolopendra subterranea_ (“Linn. Soc. Trans.” I. pp. 103–111). This was afterward translated into Italian and appeared in Vol. IX. p. 26, of Brugnatelli’s _Annali di Chimica_. Mr. James Wilson, F.R.S.E., in his “Encycl. Brit.” article on _Myriapoda_, alludes to the _Scolopendra electrica_ as figured by Frisch and described by Geoffroy in his “Histoire des Insectes,” Vol. II. p. 676, n. 5. Shaw also treats of the _Trichiurus Indicus_, which Sir David Brewster believes to be the same as the _trichiurus electricus_, known to inhabit the Indian Seas and to have the power of giving electric shocks.

Five years before the above date (1786), the _Phil. Trans._ contained (p. 382) the description of the _tetraodon electricus_, which Lieutenant William Paterson discovered in the cavities of the coral rocks of one of the Canary Islands and which he found to possess the properties of other electrical fishes. (See Hutton’s abridgments, Vol. XVI. p. 134.)

REFERENCES.--“Biographie Générale,” Vol. XLIII. p. 922;
“Gentleman’s Magazine,” Vol. LXXXIII; Poggendorff, Vol. II. p.
918; “Cat. Royal Society Sc. Papers,” Vol. V. p. 674; Dr. Thomas
Young, “Course of Lectures,” London, 1807, Vol. II. p. 436, for
the _Trichiurus Indicus_....

Having thus far called attention to the most important varieties of the electrical fishes, notably at the articles Adanson (A.D. 1751), Bancroft (A.D. 1769), Walsh, also Hunter (A.D. 1773), the following original list of additional references will prove interesting:

_Raia Torpedo._--Stephani Lorenzini, “Osservazioni ...” Firenze,
1678; R. A. F. de Réaumur, “Des Effets ...” Paris, 1714;
Templeman, in “Nouvelliste,” 1759; Ingen-housz (_Phil. Trans._,
1775); Cavendish (_Phil. Trans._, 1776, Vol. LXI. p. 584, Vol.
LXVI. p. 196, also Hutton’s abridgments, Vol. II. p. 485; Vol.
XIII. p. 223; Vol. XIV. p. 23); F. Soave (“Scelta di Opuscoli,”
Vol. XV), Milano, 1776; J. A. Garn, “De Torpedine ...” Witteb.,
1778; R. M. de Termeyer (Raccolta Ferr. di Op. Sc. ... Vol.
VIII), Venice, 1781; L. Spallanzani (“Goth. Mag.,” V. i. 41;
“Opusc. Scelti,” VI. 73), Milano, 1783; Girardi and Walter
(“Mem. Soc. Ital.,” III. 553), Verona, 1786; W. Bryant (“Tr.
Amer. Phil. Soc.,” II. 166, O. S.), Philad., 1786; J. W. Linck,
“De Raja Torpedine,” Lips., 1788; Vassalli-Eandi (_Journal de
Physique_, Vol. XLIX. p. 69); Geoffroy Saint-Hilaire (“Annal.
du Mus.,” An. XI. Vol. I., No. 5, and _Phil. Mag._, Vol. XV.
p. 126), 1803; J. F. M. Olfers, “Die Gattung Torpedo ...”
Berlin, 1831; Linari-Santi in “Bibl. Univ.,” Ser. II., Geneva,
1837–1838, and in “Bibl. Ital.,” Vol. XCII. p. 258, Milan,
1839; C. Matteucci, “Recherches ...” Genève, 1837 (“Royal Soc.
Catalogue of Sc. Papers,” Vol. IV. pp. 285–293); also Delle
Chiaje, “On the Organs ...” and P. Savi, “Etudes ...” Paris,
1844; G. Pianciani (“Mem. Soc. Ital.,” XXII. 7); F. Zantedeschi
(“Bull. Acad. Brux.,” VIII. 1841); A. Fusinieri (“Ann. del
Reg. Lomb.-Veneto,” VIII. 239), Padova, 1838; A. F. J. C.
Mayer, “Spicilegium ...” Bonnæ, 1843; L. Calamai, “Osservazioni
...” 1845; C. Robin, “Recherches ...” Paris, 1847; Krünitz,
“Abhandl.,” XVII; _Nicholson’s Journal_, Vol. I. p. 355;
Rozier, IV. p. 205; “Acad. Brux.,” 111; “Phil. Hist. and Mem.
of the Roy. Acad. of Sc. Paris,” 1742, Vol. V. pp. 58–73; John
Ewing, at A.D. 1795; Dr. Godef. Will. Schilling (in original
Latin, also the French translation), “Biblioth. Britannique,”
Vol. XL. pp. 263–272; Dr. Jan Ingen-housz in _Phil. Tr._ Vol.
LXV. p. 1; Vol. LXVIII. pp. 1022, 1027; Vol. LXIX. pp. 537,
661; also Hutton’s abridgments, Vol. XIII. p. 575; Vol. XIV.
pp. 462, 463, 589, 598; “Journal des Sçavans,” Vol. LXXVIII.
for January-April, 1726, p. 58; “The System of Natural History,
written by M. De Buffon,” Edinburgh, 1800, Vol. II. pp. 24–25.

M. R. A. F. De Réaumur, mentioned above, has communicated the
results of his investigations relative to the _torpedo_ in
“Mém. de Paris” for 1714, following it up more particularly with
another article in the issue for year 1723 on magnetization,
which is also alluded to in “Journal des Sçavans,” Vol. LXXXII.
for 1727, p. 4.

_Silurus Electricus._--Ranzi, on the discovery of the discharge
of this animal; P. Forskal “Beobachtungen ...” 1775; F. Pacini,
“Sopra l’ Organo ...” Bologna, 1846; Abd-Allatif, Relation de
l’Egypte, p. 167, quoted at p. 250; Note XI. vol. i. of Libri’s
“Hist. des Mathém.”; C. Maspero, “The Dawn of Civilization,”
New York, 1894, p. 36, wherein it is said that the silurus was
the _nârû_ of the ancient Egyptians, as described by Isidore
Geoffroy de St. Hilaire in his “Histoire Naturelle des Poissons
du Nil.”

_Gymnotus Electricus._--T. Richer, “Observations ...” Paris,
1679 (“Hist. et Mém. de l’Acad. Roy. des Sciences,” Vols. I.
p. 116; VII. i. pt. 2, p. 92); “Edinburgh Review,” Vol. XVI.
pp. 249–250; John Ewing at A.D. 1795; P. Sue, aîné “Histoire
du Galvanisme,” Paris, An. X, 1802, Vol. II. pp. 94–97; A. Van
Berkel, “Reise nach Rio ...” Memming, 1789, for the observations
made in 1680–1689; J. B. Duhamel (“Hist. Acad. Sc.,” 168); J.
N. Allamand, “On the Surinam Eel ... by S’Gravesande,” Haarlem,
1757; Gronov-Gronovius (“Acta Helvetica ...” IV. 26, Basle,
1760; _Phil. Trans._, Vol. LXV. part i. p. 94, 102, and part
ii. p. 395); P. V. Musschenbroek (“Hist. et Méms. de l’Acad.
des Sc.,” 1760); G. W. Schilling, “Diatribe de Morbo ...” 1770,
treating of the torpedo as well as of the _magnetism_ of the
Gymnotus (which latter was observed by him in 1764, and is
alluded to besides by Jan Ingen-housz in his “Nouv. Exper.,”
Paris, 1785); “Mem. of Berlin Acad. of Sc.,” Bonnefoy, “De
l’app. de l’élect ...” 1782–1783, p. 48; Ferdinando Elice,
“Saggio sull’ Elettricità,” p. 26; H. Williamson, Alexander
Garden and John Hunter in the _Phil. Trans._ for 1775, p. 94,
102, 105, 395, and in Hutton’s abridgments, Vol. XIII. pp.
597–600; R. M. de Termeyer (“Opus. Scelti,” IV. 324, for 1781);
H. C. Flagg (“Trans. Amer. Phil. Soc.,” O. S., Vol. II. p. 170);
Samuel Fahlberg, “Beskrifning ofver elektriska alen Gymnotus
electricus,” Stockholm, 1801; (See Fahlberg at A.D. 1769, and
in “Vet Acad. Nyr. Handl.”; Gilbert, _Annalen_, XIV. p. 416);
Humboldt, “Observations ... anguille elect ...” Paris, 1806;
“Versuche ... elec. fische,” Jena, 1806; also in the _Annales
de Chimie et de Physique_, Vol. XI for 1819, and at p. 256 of
the “Harmonies of Nature,” by Dr. G. Hartwig, London, 1866,
will be found a picture showing mode of capture of the Electric
Eel; F. S. Guisan, “De Gymnoto ...” Tübingen, 1819, Carl
Palmstedt (“Skand. Naturf. motets Forhand,” 1842); H. Letheby
(“Proceedings London El. Soc.,” Aug. 16, 1842, and June 17,
1843); M. Vanderlot’s work, alluded to by Humboldt at p. 88 of
his “Voyage ...”; F. Steindachner, “Die Gymnotidie ...” Wien,
1868.

Consult likewise, for reputed magnetic powers of the _echeneis_,
or sucking-fish, Gaudentius Merula, “Memorabilium,” 1556,
p. 209; Fracastorio, “De Sympathia,” lib. 1, cap. 8; W.
Charleton, “Physiologia,” 1654, p. 375; Cornelius Gemma,
“De Naturæ Divinis,” 1575, lib. 1, cap. 7, p. 123; and, for
electrical fishes generally, Rozier, Intr., II. p. 432; Bloch,
“Naturgeschichte ...” Berlin, 1786; A. De la Rive, “Traité
de l’électricité,” Paris, 1858, Vol. III. pp. 61–82; Rozier,
Vol. XXVII. pp. 139–143; “Works of Michael de Montaigne,” by
W. Hazlitt, New York, 1872, Vol. II. pp. 158–159; R. J. Haüy,
“Traité de Physique,” p. 41; Geoffroy Saint-Hilare (_Journal de
Physique_, LVI. 242; _Phil. Mag._ XV. 126–136, 261; “B. Soc.
Phil.” N. 70; Gilbert, _Annalen_, XIV. 397; “Ann. du Mus.”
for 1803); M. Schultze, “Zur Kentniss ... elect ... fische,”
Halle, 1858 and 1859; Jobert (de Lamballe) “Des Appareils ...”
Paris, 1858; W. Keferstein and D. Kupffer (Henle u. Pfeuffer’s
“Zeitschr. f. rat. Med. Newe Folgc,” III. 1858) and Keferstein’s
“Beitrag ... elekt. fische,” Göttingen, 1859; “Annual of Sc.
Discovery” for 1863, giving, at pp. 115–116, the views of
Sir John Herschel, of Charles Robin and of M. Moreau on the
electrical organs of fishes.

=A.D. 1792.=--Berlinghieri (Francesco Vacca, and not Vacca Leopold nor Andrea Vacca), Italian surgeon and anatomical writer, communicates to M. De La Méthérie the result of the extensive experiments made by him in concert with M. Pignotti and his brother. After describing his investigations with frogs, he remarks that the same movements and contractions can be produced on animals with hot blood, but that the latter require a peculiar process. He says that after having dissected the crural or any other considerable nerve, and cut it at a certain height to separate it from its superior part, it should have a piece of tinfoil wrapped around its summit, and the communication should be made in the usual way by touching the coating with one of the extremities of the exciting arc and the muscles in which the nerve is distributed with the other extremity.

Many other investigations of Berlinghieri were, later on, communicated to the Société Philomathique, by whom they were successfully renewed, and, during the year 1810, a translation of his paper on the method of imparting magnetism to a bar of iron without a magnet appeared at p. 157, Vol. XXXV. of the _Philosophical Magazine_.

REFERENCES.--Rozier, XL. p. 133, and XLI. p. 314; “Giorn. di
Med. Prac. di Brera,” IX. pp. 171–298; L. B. Phillips, “Dict. of
Biog. Ref.,” 1871, p. 137; Tipaldo, “Biografia ...” 1834.

=A.D. 1792.=--Lalande (Joseph Jérome le Français de), a distinguished scientist, and, doubtless, the best known of all French astronomers, who had previously communicated (1761) observations on the loadstone to the “Mémoires de Paris,” and had likewise written upon meteoric displays (1771), addresses to the _Journal des Sçavans_ of Nov. 1792 a treatise entitled “Une Notice sur la découverte du Galvanisme,” justifying his claim to being the first introducer of galvanism into France, which he had before made through the columns of the _Journal de Paris_ of the 17 Pluviôse, An. VII.

REFERENCES.--Lalande, “Abrégé de l’Astronomie,” pp. 101, etc.;
“Biog. Générale,” Vol. XXVIII. p. 948; “Biog. Universelle,” Vol.
XXII. pp. 603–613; Ninth “Enc. Britannica,” Vol. XIV. p. 225; P.
Sue, aîné, “Hist. du Galv.,” Paris, An. X (1802), Vol. I. p. 1.

=A.D. 1792.=--Chappe (Claude), a French mechanician (1763–1805), introduces the _sémaphore_, which he at first called a _tachygraphe_, from two Greek words meaning to write fast, but to which M. Miot, chief of one of the divisions of the War Department, gave the name of telegraph during the year 1793. Chappe had not long before devised a contrivance somewhat like that alluded to by Barthélémy (A.D. 1788), but it was not apparently brought into use.

His _sémaphore_ consisted of a vertical wooden pillar 15 feet or 16 feet high, bearing a transverse beam 11 feet or 12 feet long, which turned upon its centre and held at each extremity pivoted arms so worked by cords or levers as to admit of 256 distinct signals. The semaphores were placed upon high towers, about four miles apart, on level ground, and even as much as ten miles apart upon intervening elevations. This system of signals was presented by Chappe to the Assemblée Législative, and was originally erected during the month of August 1794 upon stations between Paris and Lille (Lisle), a distance of about 148 miles. One of the first sentences conveyed between the two places by the Committee of Public Safety consumed 13 minutes and 40 seconds, but it was not long before dispatches could be conveyed in two minutes’ time, and it was through Chappe’s apparatus that the news of the recapture of the city of Condé was conveyed to the Assembly shortly after the entry of the troops of the Republic.

It is not now believed that Claude Chappe was acquainted with the devices of either Robert Hooke (at A.D. 1684) or of Guillaume Amontons (at A.D. 1704), as was at the time claimed by many of his jealous contemporaries. No doubt exists that he is justly entitled to the credit of having, with the assistance of other members of his family, developed an entirely new system of signals as well as the mechanism by which they were operated. The histories of telegraphy written by I. U. J. Chappe (Paris, 1824; Le Mans, 1840) review Claude Chappe’s investigations and the difficulties he encountered, besides making reference to the false magnetic telegraphs of A. T. Paracelsus (A.D. 1490–1541), William Maxwell (A.D. 1679), and F. Santanelli (“Philosophiæ reconditæ ...” Coloniæ, 1723) alluded to in the “Dictionnaire des Sciences Médicales.”

Claude Chappe’s uncle, L’Abbé Jean Chappe d’Auteroche (1722–1769), French astronomer, who succeeded N. L. de la Caille at the Paris Observatory as assistant to Cassini de Thury and edited a translation of the works of Dr. Halley, is the author of several memoirs upon the declination and inclination and upon lightning, meteors, etc., alluded to in J. B. J. Delambre’s “Hist. de l’Astron. au 18^e siècle,” in J. C. Poggendorff’s “Biog.-Liter. Hand.,” Vol. I. p. 420, and in the “Mém. de Paris,” 1767, _Mém._ p. 344.

REFERENCES.--English Encycl., “Arts and Sciences,” Vol. VIII.
p. 65; “Johnson’s Encycl.,” Vol. IV. p. 757; “Penny Ency.,”
Vol. XXIV. p. 146; Shaffner, “Manual,” pp. 27, 45 and 48; “Le
Cosmos,” Paris, Feb. 4, 1905, p. 128; Nicholson’s “Journ. of
Nat. Phil.,” Vol. VIII. p. 164, note; _Sc. American Supplement_,
No. 475, p. 7579; “Emporium of Arts and Sciences,” Vol. I. p.
292; Rozier, XXXIV. p. 370, and XL. p. 329; “Bull. des Sc. de la
Société Philomathique,” March 1793, No. 21, for an account of
the experiments of Galvani and of Valli repeated for the Society
by C. Chappe, M. Robillard and A. F. de Silvestre.

=A.D. 1792.=--Valli (Eusebius), Italian physician of Pisa, corresponding member of the Royal Academy of Sciences at Turin, publishes his “Experiments on Animal Electricity” the results of which were communicated to the French Academy of Sciences and found to be of such great importance that a committee composed of Messrs. Le Roy, Vicq d’Azyr, Coulomb and Fourcroy, was directed to repeat them. The most important were repeated in Fourcroy’s laboratory on the 12th of July 1792.

Valli was the first to demonstrate that when an arc of two metals, plumber’s lead and silver, is employed upon an animal, the most violent contractions are produced while the lead is applied to the nerves and the silver to the muscles. He also showed that of all metals, zinc, when applied to the nerves, has the most remarkable power of exciting contractions; and he found that when a frog had lost its sensibility to the passage of a current, it regained it by repose.

These experiments were also repeated before the French Royal Society of Medicine. M. Mauduyt, who was present, deduced from the results obtained by Valli that the metals were charged with a different quantity of the electric fluid, in so much that when they were brought in contact with each other a discharge ensued. And, secondly, that the animal body, by which the electric fluid is rendered perceptible, is a more delicate electrometer than any one heretofore discovered.

Many new and very interesting investigations were afterward made by Valli upon different animals, the results of which were given to the public through the columns of the _Journal de Physique_ as shown below. These embrace thirteen experiments upon animals rendered insensible by means of opium and powdered tobacco, showing electricity to be independent of their vitality, as well as others to show that the electric fluid is necessary to man and animals. He fully established the identity of the nervous and the electric fluids, and proved that the convulsions took place by merely bringing the muscles themselves into contact with the nerves, without the intervention of any metal whatever. In answer to the inquiry of M. Vicq d’Azyr, member of the late French Academy of Sciences, he supported by nineteen experiments the assertion that however the blood vessels may be, as they assuredly are, conductors of electricity, the nerves alone prove capable of exciting muscular movements in consequence of the mode in which they are disposed.

REFERENCES.--Brugnatelli, _Annali di Chimica_, Vol. VII. pp.
40, 213, 228 (and pp. 138, 159, 186, 208 for Caldani); also
the “Giornale Fis. Med. di Brugnatelli,” Vol. I. p. 264; Sue,
“Histoire du Galvanisme,” Paris, An. X-1802, Vol. I. p. 45;
“Société Philomathique,” Vol. I. pp. 27, 31, 43; _Journal de
Physique_, Vol. XLI. pp. 66, 72, 185, 189, 193, 197, 200, 435;
Vol. XLII. pp. 74, 238, the last named containing the “Lettre
sur l’Electricité Animale” (“De animalis electricæ theoriæ
...” Mutinæ, 1792) sent by Valli to MM. De La Méthérie and
Desgenettes; Report of MM. Chappe, Robillard and Silvestre on
Valli’s and Galvani’s experiments (“Soc. Phil.” for March 1793,
No. 21); Report of Messrs. Le Roy, Vicq d’Azyr and Coulomb in
“Médecine éclairée par les Sciences Physiques,” Tome IV. p. 66;
“Epitome of Electricity and Magnetism,” Philad., 1809, p. 133;
“Versuche ... animal, electricität” of Karl Friedrich Kielmayer
(Kielmaier) of the Tübingen University (Poggendorff, Vol. I. p.
1253; F. A. C. Gren, _Journal der Physik_, Vol. VIII for 1794);
Floriano Caldani’s works, 1792–1795, and those of Leopoldo
Marc-Antonio Caldani, 1757–1823; Junoblowiskiana Society,
1793–1795.

=A.D. 1793.=--Fontana (Felice), distinguished Italian experimental philosopher and physiologist, gives in his “Lettere sopra l’ Elettricità Animale,” the result of further extensive investigations carried on by him to ascertain more especially all the features of galvanic irritability and the peculiar actions of the several organs in cases of death by electricity. Some of his previous observations in the same line had already been made known through his “Di Moti dell’ Iride,” 1765, and “Richerche filosofiche,” 1775, all which led to an active correspondence in after years with the Italian Giochino Carradori, as will be seen by consulting the volumes of Luigi Valentino Brugnatelli’s well-known “Giomale Fisico-Medico” (Cuvier, in “Biog. Univ.,” Vol. XV. p. 8, par. 1816; “Giornale Fisico-Medico,” Vol. IV. p. 116).

Fontana (Gregorio), younger brother of Felice Fontana, likewise an able natural philosopher, succeeded the celebrated Ruggiero Giuseppe Boscovich in the Chair of Higher Mathematics at the University of Padua, and is the author of “Disquisitiones physico-mathematicæ,” Papiæ, 1780, as well as of many papers in the “Mem. della Soc. It. delle Scienze,” wherein he gives detailed accounts of many very interesting electrical observations. Mention of Gregorio Fontana’s name has already been made under Bennet, A.D. 1787.

REFERENCES.--Houzeau et Lancaster, “Bibl. Gén.,” Vol. I. part i.
p. 334, and, for R. G. Boscovich, “The Edinburgh Encyclopædia,”
1830, Vol. III. pp. 744–749.

=A.D. 1793.=--Aldini (Giovanni), nephew of Luigi Galvani and one of the most active members of the National Institute of Italy, who succeeded his former instructor, M. Canterzani, in the Chair of Physics at the Bologna University, established in the last-named Institution a scientific society whose open object was to combat all of Volta’s works and which became very hostile to the organization already formed in the University of Pavia by Felice Fontana, Bassiano Carminati and Gioachino Carradori against the followers of Galvani. Similar societies espousing the cause of Volta were subsequently organized in England, at the suggestion of Cavallo and others, and during five years, the scientists of Europe were divided between the two discoverers, without, however, any material benefit accruing therefrom to either faction.

Aldini proved to be an indefatigable investigator, as shown by the numerous Memoirs sent by him to the publications named below, up to the month of October 1802, when he experimented before the Galvani Society of Paris. An account of these experiments is given in his “Essai théorique,” etc., where, among other results, attention is called to the curious fact that contractions can be excited in a prepared frog by holding it in the hand and plunging its nerves into the interior of a wound made in the muscle of a living animal (Figuier, “Exposition,” etc., Vol. IV. p. 308). His interesting investigations of the artificial piles of muscle and brain, first made by M. La Grave and shown to the French Galvani Society, are alluded to in _Nicholson’s Journal_, Vol. X. p. 30, in the _Journal de Physique_, An. XI. pp. 140, 159, 233, 472, and in Sturgeon’s “Scientific Researches,” Bury, 1850, p. 195.

Nearly all of Aldini’s experiments were successfully repeated in London at Mr. Wilson’s Anatomical Theatre, where Mr. Cuthbertson assisted Prof. Aldini in arranging the apparatus, and where a student, by the name of Hutchins, furnished the anatomical preparations, but the demonstration, of all others, which attracted most attention was doubtless the one made in London on the 17th of January 1803. The murderer Forster had just been executed and, after his body lay for one hour exposed in the cold at Newgate, it was handed over to Mr. Koate, President of the London College of Surgeons, who, with Aldini, made upon it numerous important observations to ascertain the precise effects of galvanism with a voltaic column of one hundred and twenty copper and zinc couples. The extraordinary results obtained, which cannot properly be enumerated here, are to be found in the “Essai Théorique,” etc., already alluded to. They led Aldini to believe he could, by the galvanic agency, bring back those in whom life was not totally extinct, such as in cases of the recently drowned or asphyxiated. (Consult M. Bonnejoy’s method of proving death by ... Faradization, Paris, 1866, and Georgio Anselmo, “Effets du Galvanisme ...” Turin, 1803; S. T. Sömmering, “On the application of Galvanism to ascertain the reality of death,” Ludwig scripter nevrolog., III. 23; Ure, “Exper. on the body of a criminal ...” “Journal of Sc. and Arts,” No. XII; _Phil. Mag._, Vol. LIII. p. 56; Jean Janin de Combe Blanche, “Sur les causes,” etc., Paris, 1773 (hanging); C. W. Hufeland, 1783, for the app. of Elec. in cases of asphyxia; T. Kerner, for the app. of Galv. and Magn. as restoratives, Cannstadt, 1858; Wm. Henley, for electricity as a stimulant ... drowned or ... suffocated, “Trans. of the Humane Society,” Vol. I. p. 63.)

Another of Aldini’s curious experiments was the production of very powerful muscular contractions upon the heads of oxen and other animals recently decapitated, by introducing into one of the ears a wire connecting with one of the battery poles and into the nostrils or tongue a wire communicating with the other pole. Thus were the eyes made repeatedly to open and roll in their orbits while the ears would shake, the tongue move and the nostrils dilate very perceptibly (De la Rive, “A Treatise on Electricity,” 1856, Vol. II. p. 489, and 1858, Vol. III. p. 588; Pepper, “Voltaic Electricity,” 1869, pp. 287, 288). In the experiments which Aldini made during 1804 upon corpses, the body became violently agitated and even raised itself as if about to walk, the arms alternately rose and fell and the forearm was made to hold a weight of several pounds, while the fists clenched and beat violently the table upon which the body lay. Natural respiration was also artificially re-established and, through pressure exerted against the ribs, a lighted candle placed before the mouth was several times extinguished.

For the experiments of the eminent French physiologist and anatomist Marie François Xavier Bichat, of Vassalli-Eandi, Giulio, Rossi, Nysten, Hallé, Mezzini, Klein, Bonnet, Pajot-Laforest, Dudoyon, Berlinghieri, Fontana, Petit-Radel, Alizeau, Lamartillière, Guillotin, Nauche and others upon animals and men recently decapitated, see Bichat’s “Recherches Physiologiques sur la vie et la mort,” Paris, 1805; Francesco Rossi’s “Rapport des expériences,” etc., Turin, 1803; P. H. Nysten’s “Nouvelles Expériences Galvaniques,” etc., Paris, 1811, and also the latter’s “Expériences faites ... le 14 Brumaire, An. XI.” (Consult likewise, J. R. P. Bardenot, “Les Recherches ... refutées,” Paris, 1824, and, for an account of Bichat consult F. R. Buisson, “Précis historique ...” Paris, 1802; Larousse, Vol. II. pp. 703, 704; “Biog. Univ.,” Vol. XI. pp. 2–19.)

In Aldini’s “Account of Galvanism,” printed for Cuthell and Martin, London, 1803, it is said (p. 218) that, on the 27th of February 1803, he transmitted current through a battery of eighty silver and zinc plates from the West Mole of Calais harbour to Fort Rouge, by means of a wire supported on the masts of boats, and made it return through two hundred feet of intervening water.

REFERENCES.--J. B. Van Mons’ treatise on animal electricity in
Tome III of the sixth year of the “Magasin Encyclopédique”;
Fowler, in “Bibl. Britannica,” May 1796; Giulio e Rossi (“Gior.
Fis. Med. di Brugnatelli,” 1793, Vol. I. p. 82); P. Sue, ainé,
“Hist. du Galvanisme,” Paris, An. X, 1802, Vol. I. pp. 31, 67,
73; Vol. II. p. 268; Brugnatelli, _Annali di Chimica_, Vols.
XIII. p. 135; XIV. p. 174; XIX. pp. 29, 158; “Opuscoli Scelti,”
Vols. XVII. p. 231; XIX. p. 217; XX. p. 73; XXI. p. 412; “Mem.
Soc. Ital.,” Vol. XIV. p. 239; Poggendorff, Vol. I. p. 27;
“Bibl. Britan.,” Vol. XXII. 1803, pp. 249–266; “Galvanische und
elektrische ... Körpern,” 4to, Frankfort, 1804; “Bull. des Sc.
de la Soc. Philom.,” No. 68; J. C. Carpue, “Bibl. Britannica,”
Nos. 207, 208, p. 373; _Phil. Mag._, Vols. XIV. pp. 88, 191,
288, 364; XV. pp. 40, 93; Cassius Larcher, M. Daubancourt et
M. Zanetti, ainé (_Ann. de Chimie_, Vol. XLV. p. 195); also
Larcher, Daubancourt et M. de Saintiot (Précis succinct, etc.,
Paris, 1803); W. Sturgeon, “Scientific Researches,” Bury, 1850,
p. 194; M. Kilian, “Versuche über restitution ...” Giessen,
1857; Gilbert, IV. 246; J. Tourdes (“Décade Philos.” No. 3,
An. X. p. 118); Francesco Rossi (“Bibl. Ital.,” Vol. I. p.
106; _Phil. Mag._, Vol. XVIII. p. 131; and in the “Mémoires
de Turin”); J. J. Sue, “Recherches Physiol.,” etc., 1803, p.
77; Vassalli-Eandi (“Expériences sur les décapités ...” Turin,
1802 and “Recueil ... de Sédillot,” Vol. II. p. 266); C. H.
Wilkinson, “Elements of Galvanism,” etc., London, 1804, 2
Vols. _passim_; Report of MM. Chappe, Robillard and Silvestre
(“Bull. des Sciences de la Soc. Philom.,” No. 21 for March
1793; also _Jour. de Phys._, Vol. XLII. p. 289); M. Payssé
(“Jour. de la Soc. de Pharm.,” first year, p. 100); Dr. Crichton
(“Rec. Périod. de Litt. Méd. Etrangère,” Tome II. p. 342);
J. Louis Gauthier, “Dissertatio,” etc., Hales, 1793 (“Com.
de Leipzig,” Tome XXXVI. p. 473); Gardiner’s “Observ. on the
animal œconomy”; Humboldt (“Soc. Philom.,” Vol. I. p. 92); Alex.
Monro’s “Experiments,” etc., Edin., 1793, 1794 (“Trans. Edin.
Roy. Soc.,” Vol. III); Felice Fontana, “Lettere ...” 1793;
Joseph Izarn, “Manuel du Galvanisme,” Paris, An. XII, 1804,
pp. 97, 138, 141, 160, 163, 285; Louis Figuier, “Exposition et
Histoire,” Vol. IV. pp. 307–308, 358, 360–363, 365, 366, 370,
371.

=A.D. 1793.=--Fowler (Richard), a very ingenious physician, of Salisbury, makes known in Edinburgh his “Experiments and Observations relative to the influence lately discovered by Galvani and commonly called Animal Electricity,” of which a very complete review is made by Dr. G. Gregory at pp. 374–381, Vol. I of his “Economy of Nature,” etc., third edition, published in London during the year 1804.

Dr. Fowler observed that the contractions in a frog are excited by making the metals touch under water even at the distance of an inch from the divided spine of the animal. He succeeded in causing the heart to contract, but could not produce the same effect upon the stomach and intestines. He also found, as did Prof. John Robison, of Edinburgh, at the same period, that the senses of touch and smell are unaffected by the metals, but that when these are applied to the eye, or, what is better, when they are thrust up between the teeth and the lips, and then made to touch, a flash of light is rendered visible. This is the case also when the metals are placed between the gums and the upper and lower lips, as proven by the experiments of Dr. Rutherford and of Mr. George Hunter, of York. Fowler likewise observed that all pure metals prove excellent conductors of the galvanic influence and that living vegetables afford it a ready passage, but that stones and oils seem to be possessed of no conducting power whatsoever.

In conjunction with Mr. Alexander Munro, Fowler published a work on animal electricity (translated into German under the title of “Abhandlung ueber thierische elekt.” etc.), while, in the “Bibliotheca Britannica” for May 1796, mention will be found of the observations of Dr. Fowler respecting the muscular irritability excited by electricity, as well as on the reproduction of the nervous substance, on the action of poisons, on the phenomena of muscular contraction, etc. etc.

REFERENCES.--“Essays and Observations,” etc., Edinburgh, 1793,
in Library of the Royal Institution; Gilbert Blane’s paper read
to the English Royal Society, of which an extract can be found
in Bacher’s “Medical Journal,” Vol. XC. p. 127; Figuier, “Exp.
et Hist. des Princip. Déc.,” Vol. IV. p. 309; C. H. Wilkinson,
“Elements of Galvanism,” London, 1804, Chap. VI. _et passim_;
eighth “Encyc. Brit.,” Vol. XXI. p. 634.

=A.D. 1793.=--Dalton (John), LL.D., F.R.S. (1766–1844), a very able English natural philosopher and the illustrious author of the “Atomic Theory of Chemistry and of the Constitution of Mixed Gases,” gives in his earliest separate publication, “Meteorological Observations and Essays,” the result of many experiments upon the electricity of the atmosphere, made by him at Kendal and at Keswick during the seven years ending May 1793.

He proved, as Sir David Brewster expresses it, that the aurora exercises an irregular action on the magnetic needle, that the luminous beams of the aurora borealis are parallel to the dipping needle; that the rainbow-like arches cross the magnetic meridian at right angles; that the broad arch of the horizontal light is bisected by the magnetic meridian; and that the boundary of a limited aurora is half the circumference of a great circle crossing the magnetic meridian at right angles, the beams perpendicular to the horizon being only those on the magnetic meridian.

In the eighth “Encyclopædia Britannica” (Vol. IV. p. 246), treating of the height of polar lights, reference is made to the extraordinary aurora borealis observed by Dalton on the 29th of March 1826, and of which a description is given in a paper read before the Royal Society, April 17, 1828 (_Phil. Mag. or Annals_, Vol. IV. p. 418; _Philosophical Transactions_ for 1828, Part II; James Hoy in _Phil. Mag._, Vol. LI. p. 422; J. Farquharson in _Phil. Trans._ for 1839, p. 267). This aurora was seen in places one hundred and seventy miles apart and covered an area of 7000 to 8000 square miles. In Vol. XIV of the same Encyclopædia will be found (p. 15), an account of another aurora observed at Kendal, February 12, 1793, while at p. 12 are given Dalton’s views as to the connection between the heat and magnetism of the earth, and, at p. 66, his conclusions as to the cause of the aurora and its magnetic influence.