BACTERIA IN CHEESE 431 
burn and Doane (1909) have mentioned and reviewed some of the 
work which was carried on previous to their publication. Hormann 
and Morgenroth (1898) upon examination of 15 samples of cottage 
cheese found 3 of which contained tubercle bacilli. Rabinowitch (1907) 
reported 3 positive samples out of 5 of the same product. Three sam- 
ples of soft cheese purchased from the Berne markets by Harrison 
(1900) were found to produce tuberculosis when injected into guinea 
pigs. Heim (1889) and Galtier (1887) infected milk before making 
cheese. Heim reported tubercle bacilli in the cheese for fourteen days 
but none after four weeks. Galtier found tubercle bacilli in cheese 
which was two months and ten days old. He believes that such milk 
products may disseminate the disease among human beings, Mohler, 
Washburn and Doane (1911) prepared a cheese from infected milk and, 
by inoculation into guinea pigs, produced generalized tuberculosis from 
samples 220 days old. Injections of emulsions 260 days old caused 
slight lesions. Schroeder and Brett (1918) carried out an extensive 
piece of work which has greatly enriched our knowledge. They pur- 
chased 256 samples of cheese from the Washington market and sub- 
jected them to examinations for the presence of tubercle bacilli by means 
of guinea-pig inoculation. Nineteen or 7.42 per cent contained tubercle 
bacili. Cheddar cheese was examined to the extent of 59 specimens; 
no tubercle bacilli were found. None were found in 32 specimens of 
Neufchatel cheese. Eighteen out of 131 samples of cream cheese were 
infectel. They regard the danger of eating ripened cheese as very 
slight since the bacilli would die during the ripening process. According 
to Mohler’s work, this would depend on the length of the ripening period. 
Rowland (1895) inoculated cheese and butter with M. cholere and B. 
typhi. After a few days no living organisms could be found, which is 
regarded as reassuring by this author. He used cheddar, Dutch and 
American cheeses and both fresh and salt butter. 
Cheese Poisoning. This type of food poisoning is said to be rather 
common. Vaughn named the poisonous substance in cheese tyrotoxi- 
con which he regarded as a ptomaine. Newman (1902) and Lepierre 
(1894) confirmed his work. Spica (1910) recently isolated a poisonous 
substance from cheese. Levin (1917) studied this subject and found 
by means of agglutination reactions that a member of the colon group 
was involved in a case of cheese poisoning, which he investigated. No 
tyrotoxicon could be found. 
Determination of the Number of Bacteriain Cheese. (Harding and 
Prucha’s Method.) Remove a square inch of the rind by means of a 
sterile knife. Draw out a plug about 4 ins. long with a carefully famed 
