DISEASES OF THE OX AND SHEEP. 347 



the children of the employes. The farmer had carried out every 

 suggestion made to him ; and, in short, he had taken every 

 precaution to secure his farm and his milk against any known 

 fault. He had a separate shed for any sick animal, and another 

 separate shed for newly arrived animals, wherein they could 

 be observed before being added to the large sheds. 



After a most searching inquiry, it seemed probable that the 

 scarlatina had not arisen from any faults in the water or the 

 drainage, nor to careless handling of milk or milk-utensils by 

 persons who might thereby have conveyed to it the virus of 

 scarlatina, but that the cows themselves must have had something 

 to do with it ; and this conclusion did not seem to be put out of 

 court by the confident affirmation that for months past not one 

 of the cows had suffered any illness. Now, it transpired that on 

 November 15th three cows which had recently calved had arrived 

 from Derbyshire and been added to the dairy farm, and it was 

 known that the first occurrences of scarlatina had taken place 

 at about the end of that same month. 



The exact date at which the milk of these cows had been used 

 could not be elicited. True, they were placed in the general 

 cow-sheds towards the close of the month ; but very probably 

 their milk, as was customary, had been used while they were 

 still quartered in " the quarantine shed." Possibly, then, we 

 may conclude that a week may have elapsed between the arrival 

 of the cows at the farm and the distribution of their milk to the 

 districts supplied, and thus, the period of incubation of scarlatina 

 being less than a week, the approximate coincidence in point of 

 time between the use of this milk from the three cows aforesaid 

 and the occurrence of scarlatina in the four milk districts was 

 most remarkable. 



There were, however, far more exact concurrences between the 

 distribution of the milk and the occurrence of scarlatina, and 

 thus Mr. Power at length reached the point of excluding external 

 scarlatina, of associating the importation of particular cows into 

 the Hendon farm with the presence of scarlatina in London 

 districts, and of connecting the milk furnished by those cows 

 with the peculiarities of the prevalence of scarlatina among con- 

 sumers of the Hendon farmer's milk. It was thought that the 

 cows added on November 15th had some kind of cow disease, 

 probably of an infective nature. 



