STARVATION 



103 



drawn upon as the fast progresses, or, assuming the purine content of 

 the tissues to be constant and that there be a steady total catabolism of 

 these tissues, that there is retention of part of the protein nitrogenous 

 constituents, as in the case of creatine. In their experiments on La 

 Tosca, Van Hoogenhuyze and Verploegh (201) also observed the 

 gradual rise in the output of purine after a short preliminary fall. 



The Output of Sulphur. 



As stated already, the investigation of the sulphur output yields a 

 certain amount of evidence as to the course of protein metabolism. It 

 will be recalled that Von Wendt (419 A) went so far as to maintain 

 that it was only by considering the output of sulphur in relation to the 

 output of nitrogen that a true idea of the course of protein metabolism 

 could be obtained (p. 87). The course of sulphur output in starvation 

 has been the subject of investigation on two or three occasions. As the 

 ratio of nitrogen to sulphur in muscle is as 14 : I the figures obtained 

 in starvation bear out the statement that a large part of the protein 

 supply in this condition comes from muscle tissue. In my investiga- 

 tion the ratio of nitrogen to sulphur gradually fell during the course 

 of the fast from about 17 to I to 14-5 to I. Halpern (165) found at 

 the end of a fast of twenty days a nitrogen: sulphur ratio of 14-61 

 to I. Presumably, then, towards the end of the fourteen-day fast of 

 Beaut6 the main source of protein supply was muscle. As the out- 



