APPENDIX C. \\ 



Ammoniac al Solutions boiled (at 212 jF.), and exposed to 

 Air in Flasks whose open necks were only loosely covered with 

 Paper Caps: subsequent Inoculation. (Temp. 75- 8 5 Fl) 



No. LIX. Ammonic Tartrate Solution. The fluid 

 remained quite clear, and free from all trace of turbidity up 

 to the ninth day, when it was inoculated with some living 

 Bacteria. In fifty hours after the inoculation there was a very 

 faint opalescence of the fluid, which, in another twenty-four 

 hours, had become much more marked. On microscopical 

 examination it was found to contain multitudes of Bacteria. 



No. LX. Ammonic Tartrate and Sodic Phosphate 

 Solution. After four days the fluid was still quite clear. 

 In seven days no trace of general turbidity, though there 

 was a minute dirty-grey aggregation, about y 1 ^" in diameter, 

 at the bottom of the flask. On the sixteenth day the grey 

 aggregation had very slightly increased in size, though the 

 fluid above was still perfectly clear. The grey mass was re- 

 moved by a small pipette, and, on microscopical examination, 

 it was found to be composed of an aggregation of minute 

 extraneous fibres, mixed with blackish particles and amor- 

 phous granular matter, in which were growing many Torula- 

 cells in all stages of development, and also a minute mycelium 

 composed of branched Leptothrix-\&& fibres 1 . The clear 

 fluid was then inoculated with some living Bacteria, and the 

 bulb of the flask was replaced in the warm-bath. After fifty 

 hours the solution showed a bluish turbidity, which, in thirty- 

 six hours more, had increased to a well-marked whitish 



simple (uninoculated) solutions would become turbid in vacua that is to 

 say, without the oxidizing influences of the air when they had not been 

 exposed to an amount of heat sufficient to destroy any living or dead 

 ferments which they might contain. 



1 A deposit of this kind is almost invariably found in such solutions 

 after their degree of fermentability has been lowered by previous boiling. 

 Growth takes place very slowly in these cases. 



d 2 



