302 AMERICAN FARMEE'S HORSE BOOK. 



times exist there for a long time, without seriously injuring 

 the horse. But we have many doubts whether they can long 

 remain there without some growth, some increase in size, 

 though it be very slowly. Almost any irritating cause may 

 occasion their enlargement. Exposure, colds, extra labor, 

 derangement of the stomach and bowels, a general feverish 

 condition of the system, and certain specific diseases, may 

 send such unhealthy influences to the lungs through the blood 

 as to excite tubercular growth and the formation of matter. 

 The healthy parts of the lung are involved by degrees^ and 

 gradually destroyed ; and now consumption has fairly entered 

 on its fell career. The yellow, almost purulent, mucus raised 

 from the lungs is the pus of the tubercles, which has burst 

 through their cells into the air-passages of the lungs, when 

 it is expectorated by the human patient, and in the horse es- 

 capes through the nostrils. 



The reader must bear in mind, that in the foregoing de- 

 scription, the tubercles have been supposed to originate in 

 the diseased condition of the lungs consequent upon- pneu- 

 monia, bronchitis, or pleurisy; but this does not imply 

 that consumption invariably follows those disorders, or even 

 that their tubercular formations necessarily produce it. [N'or 

 do we wish to be understood to say that tubercles may not 

 exist in the lungs of the horse quite independent of them, 

 and indeed of all other aifections. 'We are satisfied that they 

 may so exist, and that consumption may establish itself in the 

 lungs as a primary disease. Perhaps the latent virus of 

 scrofula is the not uncommon, though seldom suspected, in- 

 strumentality which develops consumption in many of these 

 cases. * • ' 



The symptoms of consumption do not vary much from 

 those of inflammation of the lungs, except in intensity. 

 There is a much slower but still more morbid action going 

 on in the lungs ; the pulse is feeble ; the nose, ears, legs, and 

 even the skin, constantly feel not only chilly, but of a clammy, 

 death-like coldness ; the membrane of the nose is of a pale 

 and ashy color; the breath is hot and very oflensive ; there is 



