414 APPLIED BACTERIOLOGY 



increased to 34,000 per c.c. ; after nine hours the increase 

 was to over 100,000, which became over 4,000,000 after 

 twenty-four hours. S. Rowland, after examining a number 

 of milks purchased in various shops in London, found that 

 they contained on the average 500,000 organisms per c.c. 

 Drs. Stewart and Buchanan Young have recently examined 

 the milk-supply of Edinburgh. Since November, 1894, 

 they have examined three hundred samples of milk from 

 iifty dairies scattered throughout the city. It was found 

 that three hours after milking there were in the winter, on 

 an average, 24,000 bacteria per c.c; in spring and early 

 summer 44,000; in late summer and autumn 173,000. 

 It was found that in dairies supplied with milk from the 

 country the average number of micro-organisms contained 

 therein five hours after milking was 41,000 per cc, while 

 in dairies supplied from town cowkeepers the average 

 was 352,000 per cc. Numerous other investigators have 

 published similar results, which show how universally 

 milk-supplies are bacterially contaminated as the result 

 of the primitive and insanitary methods employed in their 

 collection and storage. 



Milk is a frequent source of infection of such diseases as 

 tuberculosis, typhoid, diphtheria, and scarlet-fever. This 

 source of conveyance of disease has already been discussed 

 under their respective headings. 



Fifteen epidemics of diphtheria, thirty-two epidemics of 

 scarlet-fever, and forty-eight epidemics of typhoid-fever, 

 have been recorded since 1881 as directly due to con- 

 taminated milk-supplies, by Dr. E. Hart, in the pages of the 

 British Medical Journal. See the reprinted ' Report on 

 the Influence of Milk in the Spreading of Zymotic Diseases ' 

 for the detailed reports of the individual outbreaks. 



As already shown, the typhoid bacillus and the cholera 

 spirillum are capable of rapid multiplication in milk, with- 



