MAWSON & SWAN, 



Bunseris Batteries. These consist of an outer cell of glass or earthen- 

 ware, with a cylinder or curved plate of zinc, within which is 

 a porous jar and block or plate of carbon. The exciting fluids 

 are diluted sulphuric acid jn the outer, and strong nitric acid in 

 the inner jar. Complete with clamps, &c., best make. (Fig. 88.) 



4J X rfe X i^g- 4^Xi|xf 6fxigxgin. 



4/~ 5,- 6/6 



Size of Carbon 2JX T yx T 7 e 3J*iX 

 Price each element 2,6 3.'- 



FIG. 88. FIG. 89. FIG. 90. 



With flat outer cell, bent zinc plate (Fig. 89), 5/- each. 



Cheaper form, round earthen or glass jar, zinc cylinder, without 

 clamp, but with copper strap soldered upon. (Fig. 90.) 

 Height in inches 3 4 5J 6j- 7 8 8 10 12 

 Price each - -2;- 3/- 4/6 5/- 6/6 8/- io/r i2/- 18/6 



Ten Cell Bunsen Battery in Tray, 2 155. 

 Arrangements smaller or larger to order. 



Groves Batteries. These consist of a square glass or earthen outer 

 cell with a bent zinc plate, a flat porous cell with a sheet of 

 platinum within; it thus resembles the Bunsen form, platinum 

 being substituted for the carbon; the exciting fluids are the 

 same as for Bunsen's. Price 9 '- per cell, pint size. In trays of 

 four, 38'-; in trays often, 84 -; superior finish, io5/- 



DanicU's Batteries. Outer cell copper, porous jar with zinc rod, 

 exciting fluids, solution of copper sulphate in the copper cell, 

 diluted sulphuric acid in the porous cell. Pint size, 4/6; 

 quart size, 6 6 



13 and 15, Mosley-street, Nezvcastle-on-Tyne. 



