68 ELECTROTYPE PROCESSES. 



By single cell apparatus, one pound of deposited copper cost 



a. d. 



lib. Sulphuric acid 02 



l T L-lb. of amalgamated zinc 8|- 



41b. Sulphate copper 16 



2 4 

 Time, at halfpenny per hour 11 



4 3 



By Daniell's battery, one pound of deposited copper cost 



l T 2 -lb. Amalgamated zinc 09 



41b. Sulphate of copper 16 



lib. Copper from electrode 10 



Sulphuric acid 01 



3 4 

 Time, at halfpenny per hour ........ 2 QJ 



5 *i 



By Smee's battery, one pound of deposited copper cost 



l-|lb. Amalgamated zinc ....... 10 



31b. Sulphuric acid ......... 06 



lib. Copper from electrode ...... 10 



2 4 

 Time, at halfpenny per hour ..... . . . . 6 1^ 



8 5J 



By Wollaston's battery, one pound of deposited copper, cost 



lib. Copper from electrode ...... 10 



. Amalgamated zinc ...... 09 



uric acid ........ 06 



. 



ly^lb. Am 

 31b. Sulph 



2 3 



Time, at halfpenny per hour ........ 6 3 



By thus adding the time, at a given rate, it serves to illustrate 

 what we have before stated respecting the necessity of placing the 

 value of time against the cost of materials. In Manufactories, where 

 time has to be paid for, it may be cheapest to use the battery with 

 the most costly materials; but where time is of no consideration, or, 



