COUGHING. A COLU, ITS PROGRESS. 33 



called, *' to cough him." No certainty, however, lies in this imagined test 

 of his wind ; for, although a thoroughly broken-winded horse will not ccugh, 

 yet one which is partially affected will do so in most instances; whilst the 

 soundest horses do most obstinately resist the coughing ; and in a few, the cir 

 cular cartilages so well defend the muscle, as to defy the inhuman effort, and 

 seem to rebuke the ignorant attempt "to prove the goodness of his wind." 



34. Farther towards its lower extremity, the wind-pipe becomes more mem- 

 branous, but less sensible of injury, and the cartilaginous rings gradually lose 

 their form : they no longer describe a circle, being composed almost wholly 

 of strong elastic membrane, that it may bend out of the way when the gullet 

 is distended with swallowing. Its internal surface is Uned with a membrane, 

 which incessantly secretes a quantity of the mucous fluid spoken of in sec- 

 tions 20 and 21, hereby defending its coats from the action of the air in pass- 

 ing to and from the lungs. But this secretion being exhausted, sometimes by 

 the very great exertions of the animal, he then coughs so as to shake his en- 

 tire frame, as if to incite the membrane to make fresh secretions of fluid for it3 

 defence; or, in default thereof, the cold air still rushing in at each inspiration, 

 he contracts a permanent cold, or catarrh, which, if suffered to continue, in- 

 creases and runs along the membrane to the lower branches of the pipe, and 

 ultimately communicates its baleful influence to one or both lobes of the lungs. 

 If the attack be trivial, small green spots are found on the surface of the lungs, 

 which afterwards form ulcers, increasing in size and number, according to the 

 number of small tubes or cells that may be affected. These tubes lose their 

 functions in consequence of the flrst attack, the animal's wind becomes worse 

 every time he is hard pushed, and the cells burst into each other, until, per- 

 haps, one lobe or half of his lungs is rendered useless. In process of time, it 

 turns black as one's hat, infects the other lobe, and mortification ensues, 

 which is rather accelerated by the cordials with which the poor creature is 

 usually punished, and it dies. 



But when it so happens, that too much of the fluid is secreted in the wind- 

 pipe, the animal snorts or coughs it off by a sudden natural effort; wherein, 

 the midriff being made to press forcibly upon the lungs, by the sudden con- 

 traction of the muscles of the lower ribs, out flies the wind through the nos- 

 trils, carrying with it whatever may have adhered by the way. Whenever 

 this is the case, the membrane that lines the nose inside becomes irritated, and 

 fresh accession of its own secretion, thickened a little, is the consequence; in 

 flammation of the part, ulcers, and a running of foul matter ensue — and this, 

 if the blood be not in a good state, soon becomes that obstinate malady — the 

 glanders. 



An instructive experiment may be made upon the pluck of a sheep — the 

 relative situation and functions of these parts in all quadrupeds being the 

 same, except that the sheep's lights, compared to those of the horse are not 

 so long in proportion to their thickness. Take a pair of bellows, and having 

 introduced the nozzle tolerably well into the windpipe, tie it round with a colv 

 bier's end; then, blowing hard with one hand, while the other is employed in 

 squeezing the pipe, to prevent the escape of the air back into the bellows, you 

 may form an accurate notion of the effect of inspiration. The lights or lungs 

 at first give out the whole of the air which has been driven in, and may be in- 

 flated to an enormous size; but, if much force is used, the cells burst intoeacli 

 other, some appearing on the surface thin and transparent, and refuse to give 

 back their wind; this forms "broken wind" of one description, and is that 

 wherein the expirations are slower than the inspirations — the pleura beiiig 

 then affected in its thickest part, and the midriff also Out of the first part 

 of this experiment may, likewise, be derived a more accurate knowledge of 

 what is termed " second wind," among sportsmen : when the animal (or iw-in) 

 5 



