ductors exists all round the circuit, and that the current is suspended only when this communication is interrupted. "This endless circulation or perpetual motion of the electric fluid," he says, "may seem paradoxical, and may prove inexplicable; but it is none the less real, and we can, so to speak, touch and handle it."
Volta announced his discovery in a letter to Sir Joseph Banks, dated from Como, March 20th, 1800. Sir Joseph, who was then President of the Royal Society, communicated the news to William Nicholson (b. 1753, d. 1815), founder of the Journal which is generally known by his name, and his friend Anthony Carlisle (b. 1768, d. 1840), afterwards a distinguished surgeon. On the 30th of the following month, Nicholson and Carlisle set up the first pile made in England. In repeating Volta's experiments, having made the contact more secure at the upper plate of the pile by placing a drop of water there, they noticed[1] a disengagement of gas round the con- «ducting wire at this point; whereupon they followed up the matter by introducing a tube of water, into which the wires from the terminals of the pile were plunged. Bubbles of an inflammable gas were liberated at one wire, while the other wire became oxidised; when platinum wires were used, oxygen and hydrogen were evolved in a free state, one at each wire. This effect, which was nothing less than the electric decomposition of water into its constituent gases, was obtained on May 2nd, 1800.[2]
Although it had long been known that frictional electricity is capable of inducing chemical action,[3] the discovery of Nicholson and Carlisle was of tho first magnitude. It was at once extended by William Cruickshank, of Woolwich (b. 1745,
- ↑ Nicholson's Journal (4to), iv, 179 (1800); Phil. Mag. vii, 337 (1800).
- ↑ It was obtained independently four months later ly J. W. Ritter.
- ↑ Beccaria (Lettere dell' elettricismo, Bologna, 1768, p. 282) had reduced mercury and other detals fron their oxides by discharges of frictional electricity; and Priestley had obtained an inflammable gas from certain organic liquids in the same way. Cavendish in 1781 had established the constitution of water by electrically exploding hydrogen and oxygen.
