30 



INJURY, RECOVERY, AND DEATH 



volving in a suitably arranged magnetic circuit such as 

 is furnished by Leeds and Northrup. The results so 

 obtained did not differ from those secured with a 

 Vreeland oscillator. 



V 



FIG. 6. Diagram to show bridge and connections. S is an alternating source (1000 eyelet 

 or more), A and B are the ratio arms of the bridge, C is the variable resistance of the bridge, 

 X it the unknown resistance (tissue and holder), T, telephone, V, variable condenser, G, a 

 ground wire from the centre of a high resistance (in case the ratio arms of the bridge are 

 unequal the two parts of the high resistance should also be unequal). 



The use of the ordinary lighting circuit (60 cycles) 

 with a vibration galvanometer is recommended by Green 

 (1917). The use of an alternating current galvanom- 

 eter in connection with a recording device is suggested 

 by Weibel and Thuras (1918). 



