On the Develojyment of B:\ctmsi in Organic Infusions. 175 



exception of Xo. 30. they were perfectly sweet and free from 

 organisms. 



So. 30 had a slightly foetid odour and swarmed with rather 

 long Bacteria — that is, Bacteria longer than the common B. termo. 

 which develops in infusions open to atmospheric air, but not quite 

 of the form of the Bacillus suhtilis of the butyric fermentation, 

 which is stated to appear in some infusions, e. y. milk, to which 

 the access of atmospheric air has been entirely prevented. It is 

 to be noticed that in this series the only retort in which Bacteria 

 made their appearance was one of those in which small hunps of 

 cheese were present during the subjection of the flask to the 

 process of ebullition and subsequent immersion in boiling water. 



This result induced us to make a further series of differential 

 experiments, bearing upon the influence of the state of aggre- 

 gation of the cheese introduced into the turnip-infusion. 



Sebies H. ]\Iarch 8th. — A turnip-infusion was prepared as in 

 Series B ; found after filtration to have sp. gr. 1113"5. 



Tubes similar to those used in Series A-E, and half filled, were 

 used. 



Tubes 42, 43, 44. The simple infusion was poured into the 

 tube, so as to half fill it ; a lump of cheese the size of a pea was 

 then added. Sealed cold. 



Tubes 4o, 40, 47. To the turuip-infusiou, before introduction 

 into the tubes, an emulsion of cheese prepared with turnip-infusion 

 and strained through a piece of cambric was added. The tubes 

 were then haK filled with this mixture and sealed cold. 



Tubes 48, 49, -50. The same as 42, 43, 44. but sealed approxi- 

 mately during ebulhtion. 



Tubes 51, .52, 53. The same as 45, 46, 47, but sealed approxi- 

 mately during ebullition. 



All the tubes, 42 to 53, were completely submerged during five 

 minutes in boiling water, and subsequently preserved in the air- 

 bath at 35° C. temperature. 



On March 13th the contents of the twelve tubes were examined 

 with the microscope. Xo. 45 had been broken in the boiling. The 

 five remaining tubes which had been prepared with cheese in the 

 finely divided condition were found to be entii'ely devoid of life, 

 the infusion microscopically and otherwise unchanged. Of the six 

 tubes prepared, each with a small lump of cheese, no organisms 

 were detected in 42 and 44 : but in 43 and 49 a few elongate 

 Bacteria were observed (in the proportion of about two to the field 

 of a Hartnack's system 10). In 48 and 50 the fluid was swarming 

 with elongate Bacteria and true Bacillus. The lumps of cheese in 

 those tubes in which life appeared had softened and spread out to 

 a certain extent on the side of the tubp. The chpese-lumps in 

 X'os. 42 and 44 retained thpir original form. 



From the result of theso later expf riments. made in conspquencr 

 of the fuller information given bv Dr. Sanderson as to Dr. Ban- 



