BACTERIA IN FOODS 2 29 



more times with sterile water, and ordinary plate cultures 

 made in Petri dishes or flat-bottomed conical flasks. The 

 colonies should be counted as late as possible; but even 

 then the isolation of pathogenic germs is uncertain. As 

 regards further procedure, the ordinary methods of sub- 

 culturing adopted in water examination must be strictly 

 followed, and the special tests for Bacillus typhosus and B. 

 coli applied. As we have already seen, the quantitative 

 estimation of organisms in milk is not of the same value as 

 in water. 



3. Inoculation. To test the capacity of the milk for caus- 

 ing disease, before or after centrifugalisation, preferably the 

 latter, a certain quantity of the sediment may be inoculated 

 into guinea-pigs. In suspected tubercle 2 cc. may be taken ; 

 in diphtheria a little less will suffice. The inoculation 

 should be either intraperitoneal or subcutaneous. Many 

 authorities hold that this test is the only safe one to protect 

 the public from milk containing germs of disease. 



BACTERIA IN OTHER FOODS 



Shell-fish have recently claimed the attention of bacterio- 

 logists, owing to the outbreak of typhoid and other epidemics 

 apparently traceable to oysters. 



It is four or five years since Professor Conn startled the 

 medical world by tracing an epidemic of typhoid fever to 

 the consumption of some uncooked oysters. 1 Almost at the 

 same time Sir William Broadbent published in the British 

 Medical Journal a series of cases occurring in his practice 

 which illustrated the same channel of infection. Since then 

 a number of similar items of evidence to the same effect 

 have cropped up. Hence there is little wonder that a num- 

 ber of investigators concentrated their attention upon this 

 matter. Professors Herdman and Boyce, of Liverpool, Dr. 

 Cartwright Wood, Dr. Klein, and Dr. Timbrell Bulstrode 



1 New York Medical Record, 1894. 



