794 EXPERIMENT STATION RECORD. 



The history of early work on this organism, technique of experiments 

 and analysis of the principal organism, and the physiological and mor- 

 phological characters of Bacillus acidi tactici as found in milk in the 

 United States are discussed at considerable length. 



As to the habitat of this organism, experiments were made with hay 

 and hay dust and with milk direct from the cows. No organisms resem- 

 bling Bacillus acidi lactici were propagated from hay or hay dust, but 

 the experiments with milk direct from the cow " suggest the possibility 

 that Bacillus acidi lactici comes from the cow in the milk duct, since its 

 maximum temperature of growth is about that of the body temperature." 



Three species of organisms were found which resembled Bacillus 

 acidi lactici so closely that the author considers them varieties of that 

 organism. The first differed, from it by not growing at 35° C, and by 

 rendering milk strongly acid without curdling it; the second was almost 

 identical with the first, except that it rendered milk only slightly acid; 

 while the third was like the second, but grew at 37.5° C. Many of the 

 samples of milk yielded a nearly pure culture of Bacillus acidi lactici. 



"It is necessary to repeat more fully the experiments in the territory covered and 

 to obtain data from other places before a valuable scientific conclusion can be drawn. 

 It is of course possible that the 47 organisms isolated are a, collection of many spe- 

 cies, but the evidence from the data obtained leaves no doubt in my mind that they 

 are the same species. 



"Milk from 30 widely separated localities in New York, Pennsylvania, Ohio, 

 Maine, New Hampshire, Massachusetts, Rhode Island, and Connecticut yielded, 

 with 2 exceptions, apparently the same organism. This fact throws the weight of 

 evidence on the side of the belief that one organism universally exists in the terri- 

 tory studied, which produces the ordinary souring and curdling of milk. This 

 organism seems to be identical in every particular with that of Giinther and Thier- 

 felder, who concluded that their organism was the same as Lister's Bacterium lactis 

 and Hueppe's Bacillus acidi lactici." 



A new milk preservative, A. W. Stokes {Analyst, 22 (1897), Dec, 

 pp.320, 321). — The "Bhodian purifier," which it was claimed would 

 keep milk sweet for several days, in the warmest weather, was found to 

 consist of potassium nitrate and water, there being 19 per cent of the 

 nitrate. It had no merits as a preservative. Its presence in milk is 

 detected when the milk solids are incinerated by deflagration, and the 

 ash if taken up in dilute sulphate gives the nitrate reactions. In test- 

 ing milk by the Gerber, Leffman-Beam, or Babcock processes a yellow 

 color appears when the milk containing this preservative is mixed with 

 strong sulphuric acid and minute bubbles of nitrous gas are given off. 



A new milk adulterant, A. W. Stokes (Analyst, 22 (1897), J><<:, 

 pp. 321, 322). — A " secret nostrum for concealing the addition of water 

 to milk" was found to contain 1.96 per cent of dextrin. It was claimed 

 that 20 per cent of water could be added to milk without fear of detec- 

 tion, provided 4 oz. of the material was added per pint of milk. It 

 was said to be used extensively in Australia. It could be detected by 

 the small amount of unaltered starch it contained, which gave the iodin 

 reaction. 



