Mr. Scrivanow's intention appears to be to apply this pile to the lighting of apartments, and even to the running of small motors, and, for the purpose of actuating sewing machines, he has already constructed a small model whose external dimensions are 160 x 100 x 90 millimeters.
"My invention," says the inventor, "is intended as an electric pile capable of regeneration. The annexed Fig. 1 shows a vertical arrangement of the apparatus, and Fig. 2 a horizontal one. In the latter, two elements are represented superposed.
"My pile consists of a prism of retort carbon (a) covered on every side with pure chloride of silver (b). The carbon thus prepared is immersed in a solution of hydrate of potassium (KHO) or of hydrate of sodium (NaHO), marking 1.30 to 1.45 by the Baumé areometer, the solvent being water.
"In the vicinity of the carbon is arranged the plate to be attacked--a plate of zinc (c) of good quality. The surface of the electrodes, and their distance apart, depends upon the effects that it is desired to obtain, and is determined in accordance with the well known principles of electro-kinetics.
"The chemical reactions that take place in this couple are multiple. In contact with a sufficiently concentrated solution of hydrate of potassium or sodium, the chloride of silver, especially if it has been recently prepared, passes partially into the state of brown or black oxide, so that the carbon becomes covered, after remaining sufficiently long in the exciting liquid, with a mixture of chloride and oxide of silver. When the circuit is closed, the chloride becomes reduced to a spongy metallic state and adheres to the surface of the carbon. At the same time the zinc passes, in the alkaline solution, into a state of chloride and of soluble combination of zinc oxide and of alkali.
"To avoid all loss of silver I cover the carbon with asbestos paper, or with cloth of the same material, d. My piles are arranged in ebonite vessels, A, which are flat, as in Fig. 1, or round, as in Fig. 2.
"In Fig 1 there is seen, at e, gutta-percha separating the zinc from the carbon at the base.
"Under such conditions, we obtain a powerful couple that possesses an electro-motive power of 1.5 to 1.8 volts, according to the concentration of the exciting liquid. The internal resistance is extremely feeble. I have obtained with piles arranged like those shown in the figures nearly 0.06 ohm, the measurements having been taken from a newly charged pile.
"When the element is used up, and, notably, when all the chloride of silver is reduced, it is only necessary to plunge the carbon with its asbestos covering (after washing it in water) into a chloridizing bath, in order to bring back the metallic silver that invests the carbon to a state of chloride, and thus restore the pile to its primitive energy. After this the carbon is washed and put back into the exciting liquid.
"These reductions of the chloride of silver during the operation of the pile can be reproduced ad infinitum, since they are accompanied by no loss of metal. The alkaline liquid is sufficient in quantity for two successive charges of the couple.