DISKASKD SIIKK.P SOF.D IX S:MITI1FIKLD. 41 



sliould have rendered it necessary for other experiments 

 to be adopted even for this pni'})ose alone ; as the cir- 

 cumstance retarded for a time our obtainini^ tliat 

 amount of practical knowledge on the subject of ovina- 

 tion which we were desirous to possess. 



While these experiments were being instituted we 

 availed ourselves of every opportunity of acquiring 

 further information, and frequently visited Datchett 

 and other places where variola had broken out ; and 

 thus investigated the progress and the symptoms of 

 the disease on the farms of different agriculturists. 

 On each succeeding market-day we inspected the sheep 

 at Smithfield, and made inquiries of salesmen and 

 others respecting the general health of their stock ; and 

 we learned that occasionally, since the middle of the 

 month of August last, many English sheep affected 

 with the small-pox had been sold to the low class 

 butchers of the metropolis. We also found that, early 

 on Monday, September 13th, a large number of such 

 sheep were thus disposed of; and although we were 

 able to trace them, we did not succeed in getting a 

 sight even of their skins. 



On Friday, September 24th, we saw in the market 

 two or three jiens of infected Downs : they were sur- 

 rounded by other sheep, and, not being sold at the 

 latter part of the day, they had been the means of 

 facilitating the extension of the malady to healthy 

 animals, as the latter had been exposed to contagion 

 for as long a time as we had proved, by experiment, 

 would be sufficient to comminiicate the disorder. Nor 

 were such instances confined to Smithfield ; for at a 

 market weekly held at Southall, in Middlesex, at which 



G 



