126 Experiments on the Development of 



No. 41 was observed to be perfectly limpid, and is so still 

 (March ITth). 



On Feb. 27th Nos. 36, 38, 39, and 40 were opened. With the 

 exception of No. 36, they were perfectly sweet and free from 

 organisms. 



No. 36 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. g. 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 lumps 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 dijfferential ex- 

 periments, bearing upon the influence of the state of aggregation of 

 the cheese introduced into the turnip- infusion. 



Series H. March 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 45, 46, 47. To the turnip-infusion, 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 half filled with this mixture and sealed cold. 



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

 proximately during ebullition. 



51, 52, 53. The same as 45, 46, 47, but sealed approximately 

 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 a microscope. No. 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 entirely 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 



