ETHER, CHLOROFORM,, ETHYL BROMIDE 



107 



the muscles'? Again lighten the anesthesia and secure 

 more "normal' 1 movements. Now give the animal a lit- 

 the (not too much) chloroform and again stimulate. Are 

 the movements affected in any way? How does this com- 

 pare with ether? If the instructor advises it the action of 

 ethyl bromide on the motor areas may be tried also. Re- 

 place the animal in the usual position and re-adjust your 

 apparatus. 



Fig. 102. "Straight" glass cannula. Several different sizes of these are often needed. 



3. Dissect out one femoral artery (Fig. 96) and place 

 in it (pointing toward the heart) a small straight cannula 

 (Fig. 102). Leave a bull-dog clamp on the artery proxi- 

 mal to the cannula. Into a test tube draw off about three 

 or four cubic centimeters of blood from the artery, and 

 at once pour an equal quantity of ether into the blood. 

 Shake the two together for a few seconds and set the tube 



Fig. 103. Hand bellows. 



aside for two or three minutes. Then observe the appear- 

 ance of the blood. Can you detect any changes? How do 

 you explain this? 



4. Kepeat this with chloroform. Do these tubes of blood 

 clot? 



5. Repeat with ethyl bromide. 



6. Cardiometer. Arrange for artificial respiration. If 



