2 THE ROYAL SOCIETY OF CANADA 



found organisms present in all cases. One was a monas (now called 

 micrococcus) and another an infusoria (a bacillus) . These observations 

 are probably the first recorded of the actual presence of bacteria in 

 milk. 



Later, some specimens of milk of a blue colour and others of a 

 yellow colour were sent to him, which, on microscopical examination 

 revealed the presence of micro-organisms. He sent some of these to 

 Ehrenbergjwho at that time was working on bacteria and this scientist 

 gave to them the names of Bacterium syncanum (subsequently called 

 B. cyanogenus by Hueppe) and Bacterium synxanthum. Fuchs 

 studied these and even cultivated them in a medium made from 

 mallow slime and actually developed the blue colour in fresh milk by 

 inoculating it with some of his culture. He found that a temperature 

 of 50-55°C would destroy the organism but that it might be frozen 

 or dried and remain alive for some time. Its growth could be inhibited 

 by chemicals. Fuchs regarded blue milk as an infection, and the only 

 means of prevention was by keeping the organisms out of the milk 

 which could be done by the exercise of care and cleanliness in the dairy 

 and by heating all utensils which had held any of the infected milk. 



Fuchs' directions for washing the hands of the milker, cleaning 

 the udders of the cow and the milk vessels as a means of preventing 

 the trouble seem quite modern and stand out with peculiar distinction 

 at a time when there was general scepticism regarding the agency of 

 living organisms as producers of fermentation. Thus in 1842 Gielen 

 denied Fuchs' conclusions and was supported in this denial by Elten 

 in 1864. Haubner attempted to show that the cause of the trouble 

 was a chemical ferment associated with the casein, and Hoffman also 

 denied the connection of blue milk with bacteria. 



In 1868, Mosler found the common blue mould present in blue 

 milk, and whilst suggesting that it might have some connection with 

 blue milk, thought that the chief effect resulted from some condition 

 of the cow. 



To return to a somewhat earlier date, we find, Blondeau in 1847 

 stating that he had discovered two micro-organisms in milk, one was a 

 yeast (Torula) and the other a mould (Pénicillium) and he thought 

 that the latter was the cause of the souring of milk through contact 

 with the milk. 



Haubner in 1852 concluded that the souring of milk was produced 

 by something outside and was a true infection similar to blue milk. 



Schlossberger in 1855 showed that milk did not sour in the udder, 

 even if allowed to remain there a long time. 



