130 



G. K STEWART 



testine segment method introduced independently by Stewart (a) (1911) 

 (Figs. 2 and 3) and by Hoskins(d) (1911-12). Stewart (a) emphasized 

 the importance in cases in which there is a possibility that the inhibition of 

 the intestine might be caused by somethng else than epinephrin of check- 

 ing the intestine reaction by a reaction such as that given by the rabbit's 

 uterus, preferably the virgin or at least the non-pregnant uterus, in which 



Fig. 3. B, bottles filled with oxygen from the oxygen cylinders 0. The oxygen 

 passes out of the bottles as water enters them from the bottles B', and is conveyed by 

 the tubes, T, to the flasks F shown in Fig. 2. 



the tone is increased by epinephrin. For instance, occasionally, as re- 

 ported by Cannon and Hoskins, the blood of the right heart or the gen- 

 eral blood in asphyxia may contain a substance which causes the char- 

 acteristic inhibition of the intestine. In such a case it has been shown 

 by Stewart that the blood inhibits the uterus preparation also, and 

 the reaction is not due to epinephrin. Although this may be occasionally 

 seen, Cannon and de la Paz are unqestionably correct in stating that, prac- 

 tically, epinephrin is the only substance in blood which causes well marked 

 inhibition of the intestine preparation. This, however, is with the proviso 

 that the tests are carried out under definite and constant conditions with 

 regard to oxygen supply, temperature, exposure of the preparation, etc. In 



