346 BACTERIOLOGY. 
greatest accumulation of toxin in bouillon is after a 
duration of growth of the culture of from five to ten 
days, according to the peculiarities of the culture em- 
ployed. At a too early period toxin has not sufficiently 
accumulated, at a too late period it has begun to de- 
generate. In our experience the amount of muscle 
sugar present in the meat makes no appreciable differ- 
ence in the toxin produced, so long as the bouillon has 
been made sufficiently alkaline to prevent the acid 
- produced by the fermentation of the sugar from pro- 
ducing in the bouillon an acidity sufficient to inhibit the 
_ growth of the bacilli. In nentral bouillon, as pointed 
out by Smith and Spronck, the sugar does produce suffi- 
cient acid to interfere with the growth of the bacilli 
and the development of toxin. This can be prevented 
by the previous destruction of the sugar through the 
fermentation caused by the growth of the colon bacilli. 
After the fermentation 0.1 per cent. of glucose should 
be added. Beside the sugar and allied bodies in the 
meat there are other substances, whose nature is un- 
known, which hinder or aid a full growth of the bacilli 
or production of toxin. This is true of bouillon made 
directly from fresh meat, fermented meat, or meat ex- 
tracts. With the meat as we obtain it in New York we 
get better results with unfermented meat than with fer- 
mented. In Boston, with the same bacillus, Smith 
gets more toxin from the fermented bouillon. Con- 
tradictory results have been obtained by others, and 
must be attributed to the difference in the materials used. 
Under the best conditions we can devise, toxin begins 
‘to be produced by bacilli from some cultures when 
freshly sown in bouillon some time during the first 
twenty-four hours; from other cultures, for reasons not 
