270 



Mr. Grove on the Gas Foliate Battery. 



paper. My grounds of dissent will be seen in some of the 

 ensuing pages. 



In describing the apparatus used in the following experi- 

 ments, I shall mention three forms of gas battery, with the 

 first two of which my experiments were all performed; the 

 latter has only occurred to me while writing this paper. I 

 have, therefore, not yet had an opportunity of trying it*, but 

 it appears to me by far the best of the three, though, doubt- 

 less, superior modifications will shortly be discovered. Fig. 1 

 represents one of these forms; a, b, c, d is a wide-mouthed 

 glass jar, into which a wooden plug, a, b, fits tightly by means 

 of attached pieces of cork ; this wooden cover is perforated to 

 receive the tubes o, k, of which the size is such that the con- 

 tent of h shall be double that of o, and which are firmly ce- 

 mented into it ; the wooden cover is shown in plan in fig. 2 ; 



Fig. 2. 



Fig. 3. 



the piece/ is capable of being detached at pleasure, in order 

 to introduce a tube for charging the apparatus with gas ; p r, 

 p' i J are strips of well- platinized platinum foil, slightly curved 

 like a cheese scoop to keep them erect and in the centre of the 

 tube, and riveted or welded to stout platinum wires, which 

 are hermetically sealed into the glass, and terminate in brass 

 mercury cups at g, g. This form of battery is charged by in- 

 verting it so as to fill the tubes with liquid; on reinversion the 

 tubes may be charged with gas from a crooked tube and blad- 

 der. The apparatus (fig. 1) is represented as charged and 

 ready for use, and in fig. 3 is a battery of five cells, also re- 

 presented as just charged. 



* See Postscript. 



