356 EXPERIMENTAL PHARMACOLOGY 



dose of cocaine to get a death record. Are convulsions pro- 

 duced? "What conclusions can you draw? Which is more 

 poisonous, cocaine or pilocarpine? 



2. After the animal dies dissect out the thoracic duct 

 at the root of the neck. See if you can do this without pene- 

 trating the chest cavity. (See Figs. 302 and 319.) Do you 

 find the lymphatic vessel coming from the head region ? 



3. Turn the body of the animal over on its side and dis- 

 sect out a section of the back bone covering two or three 

 vertebra?. Cut away the lamina? and remove the spinous 

 processes from two or three vertebra?. Can you isolate the 

 cord? How large is it? Can you make out the anterior 

 and posterior nerve roots? Locate a posterior nerve root 

 ganglion. What is the function of this ganglion? Does this 

 bear any relation to the action of cocaine? If so what? 

 Could you pass a long hypodermic needle through the skin 

 and tissues of the back down into the spinal canal ? Study 

 the anatomy of these structures carefully and try to decide 

 on what technic you would use in making a spinal puncture. 



EXPERIMENT XCVIII. 

 Novocaine. (Dog: Spinal Anesthesia.) 



(This experiment should be performed only at the discre- 

 tion of the instructor, and then by students who have 

 some knowledge of aseptic operations. It may 

 be done as a demonstration.) 



1. Sterilize by boiling in water for five minutes a good 

 hypodermic syringe having a large needle at least two 

 inches long. Prepare a novocaine solution (two per cent) 

 and sterilize it by boiling for a brief period of time. Cool 

 the solution but see that it does not become contaminated 

 with airy organisms. (Keep it in a sterile test tube plugged 

 with sterile cotton). Place on the operating table a razor 

 (clippers are also desirable), a pan of strong soapsuds, 



