5 go Balls . — Temperature and Growth . 
depressions of the stopping-point we shall be in a position to put a part of 
the growth process on a chemical footing. 
The causes which have prevented this accurate determination are three- 
fold. The body c ;u ’ has only been obtained in quantities which are relative 
to the bulk of the solution, whereas it will have to be isolated and handled 
in definite amount. The slight instability of ' x' has also to be overcome. 
Curve 4. 
Lastly, so much time was spent during the cool months of the Egyptian 
winter in devising a satisfactory apparatus for the research, that by the time 
the qualitative experiments had been carried out the summer had arrived. 
Decomposition of 1 x \ 
The first experiments with stale media gave erratic results. The cause 
of this was traced to the boiling of the media in the steam sterilizer, which 
partly, or entirely, destroyed the poisonous excreta. This is contrary to 
the opinion which I formed during the preliminary experiments with mass 
