May 3, 1901.] 
24 by 34 inches, one inch thick, and con- 
tains, for each of the six outlets to be con- 
trolled, one circle of twenty-five contact 
pieces, and has two spring levers, insulated 
from each other and moving about a com- 
mon center, sweeping over them. The con- 
tact blocks are numbered consecutively 
from 0 to 24 and a stop is provided to pre- 
SCIENCE. 701 
wire leads from the six similarly numbered 
blocks to the junction between two cells. 
In this lead is provided the usual fuse. 
The circles are lettered A, B, C, etc., con- 
secutively, corresponding with the letters 
at the outlets to be controlled. 
“Should the operator at the outlet E, for 
instance, need two cells, he goes to this 
Fig. 5. Distributing Board. 
vent the levers from sweeping past the 
zero. Cell No. 1 is connected between 
blocks numbered 0 and 1 in each of the six 
circles, cell No. 2 between blocks numbered 
1 and 2, and so on for the remainder of the 
twenty-four cells in that group, so that all 
blocks similarly numbered on the one board 
are connected together, and but a single 
board, and finding that the cells from the 
twelfth cell forward are not being used in 
any of the circles, he places one of his levers 
on contact block No. 12 and the other one 
on No.14. There is thus very little chance 
of doing anything wrong, or for persons to 
interfere with one another, because there is 
no necessity to use the same cells, and at a 
