546 



Drs. T. L. Brunton and A. Macfadyen. 



and does so more surely and quickly than the enzyme formed in 

 gelatine itself. 



2. The liquefaction is produced by a soluble ferment, since its 

 action can be demonstrated apart from the microbes which pro- 

 duce it. 



III. 



Instead of using heat sterilisation some experiments were made 

 with menthol and thymol. 



It was found that when these substances were added in amounts 

 sufficient to prevent the growth of the bacteria — the ferment action 

 was likewise inhibited. 



IV. 



The presence of a soluble ferment being demonstrated, can we 

 isolate it ? 



(1.) From gelatine. 

 (2.) From meat broth. 



(1.) From Gelatine Cultures. 



Flasks containing 250 c.c. of 10 per cent, gelatine were inoculated 

 with the five microbes. They were left in the incubator at 47° C, 

 (putrefactive micrococcus, 32° C), till liquefaction was complete. 

 The liquefied gelatine was treated with absolute alcohol and filtered. 

 The precipitate was extracted with glycerine, and finally repre- 

 cipitated with alcohol. The precipitate, after drying in a sterilised 

 flask, was taken up in a small quantity of sterile distilled water, and 

 allowed to stand over night. About 5 c.c. were then added to 10 per 

 cent, gelatine, and incubated at 37° C. 



Results. — Negative. No liquefaction was produced. 



(2.) Meat Broth Cultures. 



In each case 250 c.c. were treated in a similar manner — with 

 alcohol and glycerine, and the precipitate and sterile distilled water 

 added to 10 per cent, gelatine. 



Results : — 



Koch's spirillum ^ 



Finkler's spirillum sNo liquefaction. 



Putrefactive micrococcus J 



Scurf bacillus 1 In a few tubes the gelatine was 



Welford bacillus / viscid. The rest resolidified. 



Control plates. No colonies. 



Concluding that the prolonged method of extraction had weakened 



