No. tid-ii;'... 



Accumulators. 



855 



Batteries for School Use, with Multiple Commutator, cells 

 Figures. Fig. A shows the front closed, Fig. 

 with drop wall. 



Size 



Max. charge and discharge current) 



Amps. ) 



Capacity when discharged for 3 hours i 



Ampere hours) 



Capacity when discharged forlOhours \ 

 Ampere hours) 



List No. 



Price of a 4 -cell battery .... 60946 

 6 .... 60947 

 8 .... 60 948 

 12 .... 60949 

 16 - .... 60950 

 24 60951 



in glass vessels fitted in a solid wood box, 

 B. the same open. Fig. C shows the back 



11 



77 



77 



77 



77 

 77 

 77 

 77 

 77 



A multiple commutator in place of the plug arrangement is somewhat more expensive to use, but it ob- 

 riatea any short circuiting ami therefore the resultant ruination of the cells. When put in parallel and in groups 

 the discharge currents and the. capacity are increased while the voltage available is smaller. 



TV' uses to which the accumulators can be put are very varied. They can be employed, e. g. for feeding 

 th<- lamp for the mirror galvanometer, for driving an electric, motor for colour dis-s, (ieissler tubes, syrens or 

 double syrens; for working an induction coil, etc. etc-., and their provision cannot be too highly recommended. 

 as the teacher has always a powerful never failing source of current at his disposal. The accumulators are charged, 

 when a heavy current supply is not available, by means of one of the thermopiles described on the following 

 pag'-s, or by Bunscn Cells. As the thermopiles require no attention, the accumulators can be charged day and 

 night without interruption: the consumption of gas being extremely small. 



For following the progress of charging it is advisable to provide a voltmeter, and for the operation of 



