1889.] Electricity developed by Oxidation of Gases, fyc. 373 



portion of an ordinary binding screw (fig. 1, aa). One of the faces 

 of the coated plate was boxed in by means of thin sheet gntta-percha, 

 so as to form a shallow chamber, 6, into which hydrogen or other gas 

 could be led as required, by means of the inlet and outlet tubes, c, o ; 

 the other face was freely exposed to the air. By impregnating the 

 porous earthenware with dilute sulphuric acid, caustic soda solution, 

 or other electrolyte, and filling the chamber b with oxidisable gas 

 (hydrogen, coal-gas, carbon oxide, &c), maintaining a slow current 

 through it to prevent material alteration of the internal atmosphere 

 by diffusion and osmosis, a form of gas battery was* obtained, capable 

 of furnishing continuous currents of sufficient magnitude to effect 

 very appreciable amounts of silver deposition in a silver voltameter. 

 Obviously, by increasing the size of the plates and arranging a 

 number of cells in series, the power might be greatly augmented ; to 

 effect this we arranged a series of coated plates in a covered trough 

 or box of insulating material, so as to form partitions, and thus divide 

 the trough into chambers alternately closed in and filled with hydro- 

 gen. &c, and open to the air (fig. 2), the connexions being made as 

 indicated, the outer faces of each pair of plates thus being freely 

 exposed to the air, and the inner faces in contact with a hydrogen 

 atmosphere ; obviously, to effect this disposition an odd number of 

 chambers is requisite, including those open to the air as well as those 



