115 



originality, are summed up in Table III.^ As the table shows, tlie 

 action has a remarkable feature: while the action of other drugs 

 depends on their concentration, in this case doses varying from 8.5 

 to 140 mg per kilogram had approximately the same effect, de- 



* CO3 production was measured in groups of Swiss albino mice, each group 

 consisting of six animals. Three animals of each group received an identical 

 quantity of "thoraiine" injected subcutaneously. The other three served as 

 controls, showing the normal basal metabolic rate. The COi production was 

 measured individually in each animal. The numbers in Table III are the aver- 

 age values of the three identically treated mice. 



The apparatus used for the determination of the basal metabolic rate was 

 so simple and worked so well that it deserves a short description. Essentially, 

 the method consisted of sucking the expired air through a known amount of 

 baryta and measuring the time needed for neutralization, thymolphthalein 

 being used as indicator. In order to provide an intimate contact between 

 baryta and air, the latter was passed through a filter disk with fine pores 

 (F in Fig. 27). It was found that even this way CO? was lost, the air bubbles 



Fig. 27. Apparatus used for the measurement of CO? production in 

 mice. For explanation see text. 



