Litter, 225 



doubted that such portion of it as is deposited upon the walls and 

 ceilings must have had its origin from the urine and litter, and have 

 been previously mixed with the atmosphere. In the chapter on 

 Farcy and Glanders I have endeavoured to shew that these formida- 

 ble diseases are the ofTspring of our ordinary Stable Management, 

 and that they are more commonly originated by the system of the 

 individuals that are the subjects of them, than propagated (as is 

 usually supposed to be the case) from one Horse to another, by con- 

 tagion. And I am strongly impressed with the conviction that the 

 use of fermentable materials as Litter, when they come to be acted 

 upon by the urine and foeces of the Horse, chiefly gives rise to 

 these maladies, which so commonly baffle the utmost efforts of our 

 nrt. For, though I have adduced facts to prove that hot and vitiated 

 air has been found sufficient to excite these diseases, in the course of 

 a few hours, in the instance of several Horses which were cooped in 

 the hold of a Transport, the hatches of which were battened down, 

 yet, we are not to infer from this circum.stance, that air so spoiled, 

 would be capable .of producing either of these forms of disease, 

 in so short a space of time, except in the frames of such Horses as 

 had been previously rendered susceptible of Farcy or Glanderous 

 action, in consequence of having been subjected for a considera- 

 ble time, to the grand exciting cause of these <lisorders. Whilst at 

 the same time, I thinlc it admits almost of demonstration, that it is not 

 the mere superabundance of heat in the air of stables (whatever may 

 be imputed to the affair of its deficiency in oxygen) that is sufficient 

 to 2-enerate Fai-cv and Glanders amongst Horses ; especially if we 

 contrast the circumstance of the non-existence of those diseases on 

 the continent of Soulii America, with that of their very great fre- 



