45, CORNHILL, E.G., AND 122, REGENT STREET,^., ^LONDON. 429 



FIG. 2522. 



JFIG. 2531. 



2522 



2523 



2524 

 2525 



2526 



2527 



Each. 

 s. d 



Each. 

 a. d. 



076 10 6 



10 

 10 



Sturgeon's Cylindrical Battery, of Copper and Zinc, in 

 Stoneware pot (fig. 2511) a simple and cheap but very 

 useful battery, for elementary class instruction ; for 

 feeble but continued action solutions of either common 

 Salt or Hydrochlorate of Ammonia are to be used ; 

 and dilute Sulphuric Acid, one part strong acid to 

 ten parts water, for stronger action .... 



Calorimotor, Wollaston's, 1 pair of 6-inch zinc and 

 double copper plates, in a trough .... 



Calorimotor, Hare's, of extra large size 



Daniell's Sustaining Battery, consisting of a cylinder 

 of Zinc and Copper, separated from each other by a 

 porous earthenware tube, and excited by a solution of 

 Salt and Water, or diluted Sulphuric acid, one part 

 acid to ten parts Water, in contact with the zinc, and 

 a Saturated solution of Sulphate of Copper in the 

 other cell. Price for single cells . . 5s. 6d. 8 11 



Daniell's Battery, containing six f-lb. cells of the above, 

 in mahogany tray ....... 



Ditto ditto containing twelve 1-lb. cells, in 

 mahogany tray (fig. 2527) 



1 12 6 



440 



Daniell's Battery is the best arrangement for use where a steady and very uniform current is 

 desired for any length of time ; much used for Electro-plating, Gilding, and Electrotyping purposes. 



2528 Mullins Battery, a modification of Daniell's Cell, 

 consists of cylinders of Zinc and Copper, separated 

 from each other by Bladder or Porous Earthenware ; 

 excited by a solution of common Salt and Water in 

 contact with the Zinc and a solution of Sulphate of 

 Copper in the other cell. Single cells . . 5s. 7 15 



Larger sizes of Daniel's or Mullin's Batteries in single cells or series, to order. 



