PRE-IRRAD 



■■■RxaaHn 



BBBni 

 ■■III 



■■■■!■■■ 



■■»■ 

 ■■lilKBI 



■■^■■■1 



■■III 



■■■IIK^I 



■■i'i 



■■■■■■ ■■■^■■■■■i 



ili|ii ■■■«!■■■■■■ 



■■■■■■ ■■■■■■■■■■ 



■■nil 

 sami 



■■II 



2 hr 



B^^riiKiiii 

 ■■i»llli 

 ■■■■»^i 



10 hr 12 hr 14 hr 



Fig. 2. A composition of action potentials from the right and left sciatic nerves 

 of a frog before and after irradiation. The nerve producing the action potentials in 

 the upper section of each row was exposed to 72 krad of 910 Mev alpha particles. The 

 nerve producing the action potentials in the lower section of each row served as a 

 control. Conduction block occurred in the bombarded nerve 14 hours following irradi- 

 ation. The oscillograms have 8 units on the vertical axis and 10 units on the hori- 

 zontal axis. On the ordinate, 1 unit is equivalent to 2.5 mv; on the abscissa, 1 unit is 

 equivalent to 1 msec. 



281 



