184 



EXPERIMENTAL PHYSIOLOGY. 



arms of which plate-like electrodes are fitted and con- 

 nected with binding screws. Keep the handles of the 

 bellows pressed upon the adductor muscles by means of 

 an elastic band. Connect the receiving tambour of the 

 pince, or the nozzle of the bellows with the recording 



tambour, introducing 

 a valve, or T-tube 

 with a screw clamp, 

 into the connecting 

 elastic tube, to regu- 

 late the pressure of 

 the air within the- 

 system of tubes. 



(c.) Arrange an 

 induction machine 

 with the trigger-kev 

 of the pendulum 

 myograph in the 

 primary circuit, and 

 the pince or bellows 

 in the secondary. 

 Take a tracing in the 

 ordinary way. The 

 time relations of the 

 manner already stated 



Fig. 76. Marey's registering tambour. 

 Metallic Capsule, T, with thin india- 

 rubber stretched over it, and bearing an 

 aluminium disc, which acts upon the 

 writing-lever, H. 



contraction are determined in the 

 (Lesson XXXII). 



LESSON XXXVII. 



TWO SUCCESSIVE SHOCKS-ACTION OF 

 DRUGS ON EXCISED MUSCLE. 



1. Two Successive Shocks. Use either the pendulum or sprin- 

 myograph, preferably the former. Either instrument must bl 

 provided with two trigger-keys which are capable of bein" 

 adjusted at any required distance from each other, and opened 

 by the moving recording plate of the instrument 



