ACTION OF STRYCHNINE ON OXYGEN CONSUMPTION 229 



centimeter of adrenaline. How does this affect the record? 

 Now give a second dose (three cubic centimeters) of mor- 

 phine and see what effect this has on the rate of oxygen 

 consumption. Take three or four notches in the oxygen 

 record to get the prolonged effects of the drug. 



Now arrange for all the drum space you can command 

 and prepare to record the rate of oxygen consumption 

 after strychnine. It is to be recalled that the C0 2 exhaled 

 by the animal may vary quite as much as the rate of oxy- 

 gen consumption for short periods of time. If a consider- 

 able excess of C0 2 is excreted it can affect the record 

 somewhat before it is absorbed. Will this mean a pro- 

 longation or a shortening of the oxygen record! Will it 

 add to or subtract from the relative length of time which 

 a given injection of oxygen will last? Consider this point 

 carefully in observing the manner in which strychnine 

 acts on the metabolism. 



Arrange all writing points and inject one cubic centi- 

 meter of strychnine (one cubic centimeter equals one-half 

 milligram). Wait a little and then repeat the injection 

 (one cubic centimeter). Continue this at brief intervals, 

 recording carefully the rate of oxygen consumption all 

 the time. Be sure the animal cannot shake down your 

 apparatus when the convulsions come on. Continue giv- 

 ing strychnine until convulsions are fully developed. How 

 do these affect the rate of oxygen consumption ? What be- 

 comes of the oxygen taken up by the animal ? What is the 

 respiratory quotient? How is it determined? Examine 

 the pupils during and after a convulsion. What do you 

 observe? Crowd on ether and see if you can stop the 

 convulsions. How does this now affect the oxygen con- 

 sumption? Lighten the anesthesia and empty the strych- 

 nine out of the burette. Fill the burette with chloral hy- 

 drate solution (four per cent) and then just after a con- 

 vulsion inject one cubic centimeter of the solution. How 



