No. 60 738. 



Standard Cells, Demonstration Cells. 



845 



60730. 1:3. 



60 731. 1 : 3. 



60732. 1:2. 



60 734. 1 : 4. 



60737. 1:3. 



60 737 a. 1:6. 



60738. 1:6. 



60.731. Standard Cell (Clark's), Figure, prepared in accordance with the instructions s. d. 

 of the Eeichsanstalt, with Test Certificate. (M. P. 10 th edn., IV, 1, Fig. 489; Gan.-Eein., 



Fig. 817) 2. 0. 



60.732. Standard Cell (Weston's), Figure, with a not fully concentrated solution of cadmium 

 sulphate, Original Weston Standard Cell, with low internal resistance, without temperature 

 coefficient, usual type for precision measurements; average value of e. m. f. 1.0190 volt, 



(M. P. 10 th edn., IV, 1, Fig. 490) 2. 0. 



60.733. - - idem, double form (2 separate cells in one case) 3. 0. 



60.734. International Weston Standard Cell, Figure, prepared in accordance with the 

 specification of the International Congress of Electrical Units and Standards, London, 

 1908, with saturated cadmium sulphate solution with excess of cadmium sulphate 

 crystals; temperature coefficient: 0.004 per cent per degree, in case suitable for petroleum 



bath; without thermometer 1.15.0 



60.735. - - idem, double form (2 separate cells in one case) 2.15.0 



60.736. Thermometer, suitable for above 0. 5. 



The testing, verification and determination of temperature coefficient of cells 

 Nos. 60,732 to 60,735 by the Eeichsanstalt are carried out by the Eeichsanstalt at cus- 

 tomers' expense. 



Galvanic Demonstration-Cells. 



60.737. Zinc-Copper Cell with separate carbon electrode, Figure (Gan.-Man. Fig. 688; 

 Gan.-Eein. Fig. 803). Dilute sulphuric acid 1 : 10 is used for charging 0. 3. 



60,737 a. Demonstration Cell, Figure, for use with Holtz Clamps, without the latter 



(see Xo. 60,172, p. 799), with 2 copper plates, 1 zinc and 1 iron plate 0. 8. 



60.738. Small Voltaic Cell, as suggested by Kolbe, Figure (Kolbe-Skellon, Introduction to 

 Electricity, Part II, Fig. 85), on wood board, for charging with dilute sulphuric acid (1 : 10) 0. 2. 



01.2222, 2220, 2219. 34', 

 2221, 5760, 579>-. 



