169 
First series (2.5 cubic centimeters of milk or dilutions injected into 
guinea pigs intraperitoneally; milk from a tuberculous udder) : Un- 
diluted milk and 1 to 20, positive result ; 1 to 40 to 1 to 100, negative. 
Second series (2 cubic centimeters fluid injected intraperitoneally) : 
Undiluted milk, positive; 1 to 50 to 1 to 200, negative. 
Third series (1 cubic centimeter subcutaneously) : Undiluted milk 
and 1 to 50, positive; 1 to 100 to 1 to 1,000, negative. 
These results show the effect of dilution of infected milk by unin- 
fected milk, as it will be seen that dilutions of greater than 1 to 50 
failed to produce tuberculosis in the inoculated animals. 
In an examination of market milk from ten different sources in 
Munich, 2 cubic centimeters were injected into the peritoneum of 
guinea pigs with negative results in all cases. 
Ernst, H. C. How far may a cow be tuberculous before ber milk becomes 
dangerous as an article of food? Amer. Jour. Med. Sci., XCVIII, 1890, p. 
439. 
1. Microscopic examination of cover-glass preparations made from 
milk of tuberculous cows without udder tuberculosis. Various parts 
of milk and cream examined : 
Specimens examined 114 
Specimens containing tubercle bacilli IT 
Per cent 81. 5 
Cows examined 36 
Cows baying tubercle bacilli in milk 10 
Per cent 1 27. 7 
2. Inoculation of rabbits (method not stated) with similar milk: 
Rabbits surviving first few days, etc 49 
Rabbits becoming tuberculous 5 
Per cent 10. 2 
Cows used 13 
Cows with milk shown tuberculous 3 
Per cent 23 
3. Inoculation of guinea pigs (method not stated) with similai 
milk: 
Guinea pigs after necessary exclusions 54 
Guinea pigs becoming tuberculous 12 
Per cent ; 22 
Per cent (author says) 28.57 
Cows used 14 
Cows giving tuberculous milk 6 
Per cent _ 42. 8 
