ii8 MILK AND THE PUBLIC HEALTH chap. 



to those first described in 1885 at Hendon. It was further 

 ascertained (but with some obscurity as to precise dates and 

 particulars) that on June 7 the milk of three heifers first came 

 into use. The calf of one of these heifers (the 7-ed heifer) died 

 four to five days after it was born. All three animals presented 

 distinct evidence of a diseased condition of the teats. The three 

 animals all calved about May 24. The authors of the report 

 are of opinion that the milk of this red heifer was the cause of the 

 outbreak, or as they put it : " The circumstances are highly 

 suggestive of a special pathogenic quality of the red heifer's milk, 

 which may possibly have caused first the death of her calf, and 

 then, on the distribution of the milk in London and Surrey, 

 produced scarlet fever among consumers in those counties. It 

 would appear that June 7, the day on which the red heifer's 

 milk first came into use, was the day on which the milk from the 

 farm first showed evidence of being infective. It is probable that 

 for two or three days the property of infectiousness was confined 

 to the milk of the red heifer ; but the roan and white heifers, 

 with which the red heifer had then for some days past been closely 

 associated, must soon have become also involved. The assumption 

 that the infected milk of one or more of these heifers, after being 

 distributed on June 7, 8, 9, and 10, was for one reason or 

 another not distributed on the 11th and 12tb, but that it and the 

 milk of other cows which had now become infected was sent to 

 the depot after that date until the time of stopping of the supply 

 from the depot, would afford a satisfactory explanation of the 

 phenomena of the outbreak." 



The question of a bovine origin from these cows, or a human 

 origin from the carter, G. L., turns upon several points, of which 

 the most important is the date of origin of the outbreak. 



After careful inquiry the writers of the report concluded that 

 the distribution on June 7, 8, 9, and 10, of the milk from 

 farm X. was associated with the development of scarlet fever. 

 Also again on June 13, but not on the 11th and 12th. Since 

 the onset of the infection of the family of G. L. was the 11th to 

 1 5th June, they conclude that the milk possessed infective property 

 at least four days before the appearance of symptoms of illness in 

 any member of the milker's family. " It would appear, therefore, 

 that the cases in this milker's family were caused by drinking 

 infected milk from farm X. ; in fact, that the milk infected the 

 milker, and not the milker the milk." 



The essential fact to justify this conclusion is the date when the 

 milk was first infective. Is the data sufficient to establish the claim 

 that the milk was infective as early as June 7 1 The chief 

 grounds for fixing this date appear to be contained in the following 

 paragraph : " The information we received in the first instance was 



