BACTERIA IN ARTICLES OF FOOD. 591 



months; and the same observer found that the ordinary processes of 

 salting and smoking did not destroy the tubercle bacillus in the flesh 

 of a cow which had succumbed to tuberculosis. Beu has made cul- 

 tures from a large number of specimens of fresh, salted, and smoked 

 meats and fish, with the general result that the fresh and salted meats 

 were found to contain a limited number of bacteria of various species, 

 and that smoking for several days did not insure the destruction of 

 these microorganisms. In specimens of sausage six days' smoking 

 did not destroy a liquefying bacillus which was present, but at the 

 end of six weeks' exposure to smoke this bacillus no longer grew, 

 while a non-liquefying bacillus present in the same specimen had not 

 been destroyed. Fourteen days' smoking sufficed to destroy all the 

 microorganisms in a specimen of bacon, but this was not sufficient 

 for the interior portions of a ham. Among the bacteria obtained by 

 Beu from smoked meats he mentions the following : Staphylococcus 

 cereus albus, Proteus vulgaris, Staphylococcus pyogenes aureus, Ba- 

 cillus liquefaciens viridis, etc. The number of colonies which de- 

 veloped from a fragment, the size of a mustard seed to that of a flax- 

 seed, taken from the interior of the meats examined, was usually 

 small; and the presence of a few scattered bacteria of these common 

 species has no significance from a sanitary point of view, except as 

 showing that pathogenic bacteria may survive in infected meats after 

 they have been exposed to the usual processes of salting and smoking. 



Petri, in experiments upon the bacillus of swine plague (Schweine- 

 rothlauf), arrived at the following results : 



The flesh of swine which died of this disease preserved its infec- 

 tious properties after having been preserved in brine for several 

 months, and the same flesh salted or pickled for a month and then 

 smoked for fourteen days contained the rothlauf bacillus in a living 

 and unattenuated condition. At the end of three months virulent 

 rothlauf bacilli were still obtained from a smoked ham, but they were 

 no longer found at the end of six months. 



Schrank (1888) has made cultures from both the albumin and the 

 yolk of fresh eggs, and finds that they are free from bacteria. He 

 thinks that, as a rule, putrefactive bacteria obtain access to the inte- 

 rior through injured places in the shell, although exceptionally the 

 egg may be infected with them in the oviduct of the fowl. The usual 

 bacteria concerned in the putrefactive changes in eggs are, according 

 to the author mentioned, a variety of Proteus vulgaris and Bacillus 

 fluorescens putidus. 



Peters (1889) has studied the flora of the " sauerteig " used in 

 Germany as yeast for leavening bread. In addition to the numerous 

 cells of three species of Saccharomyces, he finds that bacilli are present 

 in great numbers, as shown by direct microscopical examination and 



