They would then enable inventors and practical men to carry out their experiments, and to put electrical matters on a proper footing. * * * * * THE FIRST EXPERIMENTS WITH THE ELECTRIC LIGHT. Electric lighting dates back, as well known; to the celebrated experiment of Sir Humphry Davy, which took place in 1809 or 1810, but the date of which is often given as 1813. There exist however, some indications that experiments on the production of the electric spark between carbons had been performed before the above named date. Mr. S.P. Thompson has given the following interesting details in regard to this subject: In looking over an old volume of the _Journal de Paris_, says he, I found under date of the 22d Ventose, year X. (March 12, 1802), the following passage, which evidently refers to an exhibition of the electric arc: "Citizen Robertson, the inventor of the phantasmagoria (magic lantern), is at present performing some interesting experiments that must doubtless advance our knowledge concerning galvanism. He has just mounted metallic piles to the number of 2,500 zinc plates and as many of rosette copper. We shall forthwith speak of his results, as well as of a new experiment that he performed yesterday with two glowing carbons. [Illustration: SIR HUMPHRY DAVY'S ELECTRIC LIGHT EXPERIMENTS IN 1813.] "The first having been placed at the base of a column of 120 zinc and silver elements, and the second communicating with the apex of the pile, they gave at the moment they were united a brilliant spark of an extreme whiteness that was seen by the entire society. Citizen Robertson will repeat this experiment on the 25th." The date generally given for the invention of the electric light by Sir Humphry Davy is 1809, but previous mentions of his experiment are found in Cuthberson's "Electricity" (1807) and in other works. In the _Philosophical Magazine_, vol. ix., p. 219, under date of Feb. 1, 1801, in a memoir by Mr. H. Moyes, of Edinburgh, relative to experiments made with the pile, we find the following passage: "When the column in question had reached the height of its power, its sparks were seen by daylight, even when they were made to jump with a piece of carbon held in the hand." [Illustration: ELECTRIC LIGHTING IN PARIS IN 1844.] In the _Journal of the Royal Institution_, vol. i. (1802), Davy describes (p. 106) a few experiments made with the pile, and says: "When, instead of metals, pieces of well calcined carbon were employed, the spark was still larger and of a clear white." On page 214 he describes and figures an apparatus for taking the galvano-electric spark into fluid and aeriform substances. This apparatus consisted of a glass tube open at the top, and having at the side a tube through which passed a wire that terminated in a carbon. Another wire, likewise terminating in carbon, traversed the bottom and was cemented in a vertical position.