132 H. J. CORPER AND H. C. SWEANY 



unable to determine whether the Hpase was freed as the result 

 of autolysis or whether it was excreted as an exo-lipase. 



The above authors (Kendall, Day and Walker, 1914d) also 

 observed that the metabolism of the smegma and grass bacillus 

 resembles that of the rapidly growing human tubercle bacillus 

 in two important particulars ; neither glucose, mannite nor glyc- 

 erin exhibits any sparing action for the protein constituents as 

 measured by the ammonia content of the broth (the ''lepra 

 bacillus" does not present this metabolic phenomenon); and a 

 rapidly growing strain of human tubercle bacilli grown in a 

 medium of very simple composition consisting essentially of 

 diammonium hydrogen-phosphat, as a combined source of 

 nitrogen and phosphorus, and glucose, mannite and glycerin 

 respectively, as a source of carbon, so changed this medium 

 that 10 per cent of the ammonium nitrogen had disappeared 

 at the end of two weeks apparently being built up into ba- 

 cillary bodies. At the end of four weeks between 40 and 

 50 per cent of the lost ammonia nitrogen reappeared in the 

 media. This occurred coincidently with the cessation of vege- 

 tative activity, strongly suggesting, as stated by the authors, 

 that it is associated with a certain amount of autolysis of the 

 bacilli, (Kendall, Day and Walker, 1914a). 



That the tubercle bacilli themselves contain enzyme inhibit- 

 ing substances was shown by Jobling and Peterson (1914) who 

 prepared unsaturated fatty acid soaps from tubercle bacilli 

 which were more actively inhibitory than soaps prepared from 

 linseed, olive and cod liver oils. 



In the following investigations it will be observed that an 

 attempt was made to check the findings obtained in every case 

 by as many methods as possible. Frequent failures marked the 

 progress of the work however, because certain of the methods 

 used were not delicate enough for the purpose and others could 

 not be used on account of interfering (absorption and turbidity) 

 phenomenon. This was especially true of the nephelometric 

 methods tried. 



