BACTERIA IN MILK OF NEW YORK 117 



bacteria indicates a favourable nidus for micro-organisms — the 

 larger the number the more favourable the nidus. And it must 

 always be borne in mind that a fluid — especially a nutritious 

 fluid like milk — which can support life in this way, even though 

 such life be represented only by saprophytic, innocent, or even 

 beneficial and economic bacteria, is a fluid which can at any 

 moment, as we shall see at a later stage, harbour and favour 

 the growth of bacteria possessing a high degree of pathogenic 

 virulence. 



As we have pointed out elsewhere, with strict precautions 

 naturally sterile milk may be obtained, and has been repeatedly 

 so obtained by us, in which no bacteria occur. Such naturally 

 sterile milk if carefully sealed remains germ-free for an indefinite 

 period, or at all events, as we found in practice, undergoes no 

 bacterial or fermentative change whatever for two years and is 

 sterile at the end of that period. Such sterile milk is obviously 

 the highest standard. But it is obtained only under exceptional 

 conditions, and the question arises. What is the best practicable 

 standard for everyday dairying ? 



An answer to this question may be obtained by a study of the 

 results of examining milk drawn with every reasonable means for 

 insuring cleanliness. On account of the exactness of the record we 

 select from many such experiments one conducted by W. H. 

 Park of New York.^ To insure cleanliness Park collected milk 

 under the following conditions : — The long hairs on the udder were 

 clipped ; the cows were roughly cleansed and placed in clean barns 

 before milking; the udders were wiped just previous to milking; the 

 hands of the men were washed and dried ; the pails used had small 

 (six-inch) openings and were thoroughly cleansed and sterilised by 

 steam before use. The milk was cooled to 45° F. within one hour 

 after milking and subsequently kept at that temperature. The 

 first six specimens were obtained from individual cows, the last six 

 from mixed milk as it flowed at diflferent times from the cooler. 



May and June ; Buchanan Young 24,000 in winter, 44,000 in spring, 173,000 

 in autumn (in Edinburgh.) Most London milks would exceed 500,000 per c.c. 

 (over 4,000,000 per c.c. has frequently been found), and we ourselves have 

 examined a large number of town and country milks having over 50,000 bacteria 

 (Bitter's Standard). A large number of similar investigations, with similar 

 results, have been made by Clauss and Hohenkamp in Wurzburg market milk ; 

 Binwid in Warsaw ; Genns in Amsterdam ; Renk in Halle milk ; Uhl in Giessen ; 

 Knochenstiem in Dorpat ; Baumann in Konisburg ; Cimningham in India ; and 

 by several investigators in London. 



^ Jour, of Hygiene^ 1901 (July), p. 393. 



