CENTRAL SCIENTIFIC CO., CHICAGO, TT. S. A. 



67 



: 



No. 964. 



No. 966A-B. 



No. 966D. 



No. 971 (with cells). 



964. BATTERY, Dry, Columbia, Red Label No. 6. The best dry cell on the market. E. M. F. on open 

 circuit, l.o ; maximum amperage, 4 to 6; E. M. F. after delivering % ampere for thirty minutes, 

 1.36 $0.40 



BATTERY, Edison Primary, the latest development, embodying all the good features of and many 

 improvements in the class of cells formerly known as the Edison Lalande and later as the Edison 

 Bsco Battery. The elements are the same as in the earlier types but the efficiency and effec- 

 tive capacity have been greatly increased by a better proportioning of active materials and by 

 an improved method of suspension. These cells are the best type of wet cell for continuous 

 service because of their very low internal resistance and ease of renewal of exhausted parts. The 

 new type of cell is contained in glass jars made of the new heat resisting glass, which possesses 

 also greater mechanical strength than the porcelain jars formerly supplied. In selecting cells 

 for laboratory use, it is important to select a sufficient number to secure the necessary voltage 

 and to select those of size and capacity great enough to deliver current at the proper rate, as 

 the larger sizes have very low internal resistance and long life and consequently operate at lowest 

 maintenance cost. Initial E. M. F., 0.95 volts, decreasing to about 0.65 on average load. 



Distinctive Features. 



(1) E. M. F. constant through life of cells. 



(2) Simplicity and ease of renewal. 



(3) Visible indication of approaching exhaustion. 



(4) Uniformity of units. . i 



(5) Long life and service. 



(6) Entire absence of local action. 



(7) Low maintenance cost. 



Xumber A B C D 



Type 202 252 402 502 



Size over all, inches 3%x6xll 3%x6xl2 5%x6%xl2i4 5%x6%xl2% 



Average internal resistance, 



ohms 0.05 0.05 0.04 0.04 



Capacity, ampere hours 200 250 400 500 



966. COMPLETE CELL 4.05 4.25 5.70 6.15 



967. COMPLETE RENEWAL ......' 2.25 2.45 3.15 3.60 



968. GLASS JAR 1.40 1.50 2.40 2.40 



969. PORCELAIN COVER .45 .45 .50 .50 



970. TERMINAL NUTS AND 



WASHERS Per set .25 25 .25 .25 



971. BATTERY TRAYS, of pressed steel heavily japanned, for use in assembling Edison primary bat- 



teries in units of various sizes. Provided with handles and with open sides for inspection of ele- 

 ments. For use only with types 202 and 252 cells. 



Number ABC 



Type 2022 2023 2024 



For cells, number 2 3 4 



Size over all, inches e^xll^xS 6Vxliy>xl2 6y,xllV>xl5% 



Each 2.40 2.70 3.00 



Number D E 



Type 2025 2026 



For cells, number 5 6 



Size over all, inches 6%xll%xl9% 



Each 3.30 3.60 



