White — Switch for Delicate Measurements. 611 



Fig. i. 

 Thermoelement bus bars 



, Locking bar 



mumSB& ' .Thermoelement bus bars 



Fig. 1. Top view and section of the universal- switch, *4 full size. Full 

 black shows copper; clear white, C, celluloid insulation; shaded, wood or 

 metal. Each of the 8 rods, when pushed forward like the second one 

 above, presses one of the wooden wedges, w, and with it two flexible flat 

 copper thermoelement leads (or leads from some other unknown E.M.F.), 

 against the thermoelement bus bars, which are copper strips connected to 

 the measuring apparatus. At the same time the pin, P 2 , in the rod, may 

 push one of the movable auxiliary -connecting frames X 1; X, against the 

 auxiliary bus bars, thus connecting in the set of potentiometer dials, or 

 other auxiliary, which it is desired to use with that particular thermo- 

 element. When P 2 is horizontal the -fixed frame, FX, makes the connection. 

 Change of combination is instantly made by rotating the rod. 



