References.—Wilkinson, “Elements of Galvanism,” 1804, Vol. II. pp. 52–63, 96–99; Pepper, “Electricity,” 1809, pp. 313–315; Noad, “Manual,” pp. 263, 264; Tomlinson, “Cyclopædia of Arts,” Vol. I. p. 566; Napier, “Electro-Metallurgy,” 1853, pp. 27, 28; Nicholson’s Journal, Vol. IV. pp. 187, 254, 261 and 511; Sturgeon’s Annals, Vol. IX. p. 309; Cruikshanks, “Some Experiments and Observations on Galvanic Electricity,” July 1800; also “Additional Remarks on Galvanic Electricity,” September 1800.
A.D. 1801.—Davy (Humphry), a very eminent English chemical philosopher, whose early studies had been greatly influenced both by Dr. John Tonkin, of Penzance, and by Gregory Watt, son of the celebrated inventor, James Watt, as well as by Mr. Davies Giddy Gilbert, who brought him to the notice of the English Royal Institution, delivers before the latter body, on the 25th of April 1801, his first lecture, wherein he traces the history of galvanism, and describes the different methods of “accumulating” it.
His first communication to the Royal Society was made in June of the same year, and is entitled, “An Account of Some Galvanic Combinations Formed by the Arrangement of Single Metallic Plates and Fluids, Analogous to the New Galvanic Apparatus of Volta.” As his able biographer, Prof. T. James Stewart Traill, M.D., of Edinburgh, remarks, this paper is the first of that series of electro-chemical investigations which have immortalized his name. In all hitherto constructed piles, the series had consisted of not less than two metals, or of one plate of metal, another of charcoal, and some interposed fluid. He showed in this paper that the usual galvanic phenomena might be energetically exhibited by a single metallic plate and two strata of different fluids, or that a battery might be constructed of one metal and two fluids, provided one of the fluids was capable of causing oxidation on one of the surfaces of the metal (“Bakerian Lectures,” London, 1840, pp. 32, etc., and Phil. Trans., Vol. XCI. p. 297).
On the 20th of November 1806 was read before the Royal Society Davy’s first Bakerian lecture, “On Some Chemical Agencies of Electricity.” This essay was universally regarded as one of the most valuable contributions thus far made to chemistry, and obtained for Davy the prize founded by Napoleon when First Consul, to be awarded by the French Institute, “à celui, qui par ses expériences et ses découvertes, fera faire a l’électricité et au galvanisme un pas comparable à celui qu’ont fait faire à ces sciences Franklin et Volta” (“Bakerian Lectures,” 1840, p. 56, and notes at p. 349, Vol. I of Dr. Lardner’s “Lectures,” etc., 1859).
Of the French Institute Davy became a member in 1817. Regarding the above-named important paper, given in full at pp. 1–56, of the volume of “Bakerian Lectures,” already referred to, Davy says (Phil. Trans. for 1826, p. 389): “Referring to my experiments of 1800, 1801 and 1802, and to a number of new facts, which showed that inflammable substances and oxygen, alkalies and acids, and oxidable and noble metals, were in electrical relations of positive and negative, I drew the conclusion that the combinations and decompositions by electricity were referable to the law of electrical attractions and repulsions,” and advanced the hypothesis “that chemical and electrical attractions were produced by the same cause, acting in the one case on particles; in the other on masses; ... and that the same property, under different modifications, was the cause of all the phenomena exhibited by different voltaic combinations” (Vol. I. pp. 678–684 of Dr. Thomas Young’s “Course of Lectures,” London, 1807, on “Electricity in Motion,” also Dr. Henry M. Noad’s “Manual,” London, 1859, pp. 362–365).
The second Bakerian lecture, “On some new phenomena of chemical changes produced by electricity, particularly the decomposition of the fixed alkalies, and the exhibition of the new substances which constitute their bases; and on the general nature of alkaline bodies,” was read Nov. 19, 1807. In this he gives an account of the most brilliant of all his discoveries (made during the previous month), proving that the so-called fixed alkalies are merely combinations of oxygen with metals. It has been stated by Dr. John Ayrton Paris that since the days of Newton no such happy and successful instance of philosophical induction has ever been afforded as that by which Davy reached the above-named results (Phil. Trans. for 1808, Vol. XCVIII. pp. 1–44). Davy’s observations were fully confirmed by Gay-Lussac, Thénard, Berzelius and Pontin (Annales de Chimie, Vol. LXXII. p. 193; Vol. LXXV. pp. 256–291; Bibl. Brit. for June 1809, p. 122). Although Davy was less successful in his attempt to decompose the proper earths, he proved that they consist of bases united to oxygen. It was reserved for Friedrich Wöhler, Berzelius and Bussy to exhibit the bases by themselves, and to show that all, excepting silica, are metallic, and capable of uniting with iron.
It is said that the original 500-plate batteries of the Royal Institution were so worn in the course of Davy’s experiments as to be almost unserviceable, and that he suggested to the managers the propriety of starting a subscription for the purchase of a large galvanic battery. This being acted upon during the month of July 1808, he was placed in possession of the battery already alluded to in the Cruikshanks article (A.D. 1800), and which was the most powerful constructed up to that time. “With this battery Davy did not reach any new results of importance; but he was enabled to demonstrate the galvanic phenomena upon a more brilliant scale. Nor was the increased power necessary to carry on successfully the experiments on the decomposition of the alkalies and the earths as was apparently believed by many of those historians of science ... who attributed the author’s brilliant success in electro-chemical research to his supposed extraordinary means, the enormous voltaic batteries of the Royal Institution.” In this connection, the terse notes appearing at foot of pp. 62, 63, 106, 107 of the 1840 edition of the “Bakerian Lectures” will prove interesting reading.
It was with the afore-named galvanic combination that Davy openly made—in 1809–1810, and not in 1813, as has been frequently stated—the first display of the continuous electric arc (John Davy, “Memoirs of the Life of Sir Humphry Davy,” p. 446).
“When the cells of this battery were filled with sixty parts of water mixed with one part of nitric acid and one part of sulphuric acid,” he says, “they afforded a series of brilliant and impressive effects. When pieces of charcoal about an inch long and one-sixth of an inch in diameter were brought near each other (within the thirtieth or fortieth part of an inch), a bright spark was produced, and more than half the volume of the charcoal became ignited to whiteness, and by withdrawing the points from each other a constant discharge took place through the heated air, in a space equal at least to four inches, producing a most brilliant ascending arch of light, broad and conical in form in the middle. When any substance was introduced into this arch, it instantly became ignited; platina melted as readily in it as wax in the flame of a common candle; quartz, the sapphire, magnesia, lime, all entered into fusion; fragments of diamond, and points of charcoal and plumbago, rapidly disappeared, and seemed to evaporate in it, even when the connection was made in a receiver exhausted by the air pump; but there was no evidence of their having previously undergone fusion” (“Elements of Chemical Philosophy,” 1812, p. 154).
Dr. Paris says that Davy had already produced the spark upon a small scale as far back as 1800 (Nicholson’s Journal, Vol. III, quarto, p. 150), and we learn, through an article published upon the early experiments with the electric light, the names of others who had likewise noticed the arc at about the same period, while Quetelet informs us that M. Curtet is reported to have observed the light between carbon points during the year 1802 (Curtet’s letter to J. B. Van Mons in the latter’s Journal de Chimie, No. VI. p. 272, and in Journal de Physique, An. XI. p. 54). The article referred to is as follows: