194 INFLAMMATION OF THE TRACHEA— ROARING. 



to abstract it; he must himself bleed, and until the pulse flutters or the constitution 

 is evidently aftected. 



Next must be given the fever medicine already recommended : the digitalis, nitre, 

 and emetic tartar, with aloes. Aloes may here be safely given, because the chest is 

 not yet implicated. To this must be added, and immediately, a blister, and a sharp 

 one. The surgeon is sure of the part, and he can bring his counter-irritant almost 

 into contact with it. 



Inflammation of the larynx, if not speedily subdued, produces sad disorganization 

 in this curiously formed and important machine. Lymph is eftused, morbidly adhe- 

 sive, and speedily organised — the membrane becomes thickened, considerably, per- 

 manently so — the submucous cellular tissue becomes cedematous ; the inflammation 

 spreads from the membrane of the larynx to the cartilages, and difficulty of breath- 

 ing, and at length confirmed roaring, ensue. 



INFLAMMATION OF THE TRACHEA. 



Inflammation of the membrane of the larynx, and especially when it has run on 

 to ulceration, may rapidly spread, and involve the greater part or the whole of the 

 lining membrane of the trachea. Auscultation will discover when this is taking 

 place. If the disease is extending down tlie trachea, it must be followed. A blis- 

 ter must reach as low as the rattling sound can be detected, and somewhat beyond 

 this. The fever medicines must be ;idniinistered in somewiiat increased doses ; and 

 the bleeding must be repeated, if the state of the pulse does not indicate the con- 

 trary. 



Generally speaking, however, althongh the inflammation is now approaching the 

 chest, its extension into the trachea is not an unfavourable symptom. It is spread 

 over a more extended surface, and is not so intense or untractable. It is involving a 

 part of the frame less complicated, and where less mischief can be effected. True, 

 if the case is neglected, it must terminate fatally ; but it is coming more within reach, 

 and more under command, and, the proper means being adopted, the change is rather 

 a favourable one. 



The disorganizations produced in the trachea are similar to some which have been 

 described in the larynx. The same formation of organised bands of coagulated 

 lymph, the same thickening of membrane, diminution of calibre, and foundation for 

 roaring. 



ROARING. 



The present will be the proper place to speak of that singular impairment of the 

 respiratory function recognised by this name. It is an unnatural, loud gnmting sound 

 made by the animal in the act of breathing when in quick action or on any sudden 

 exertion. On carefully listening to the smnnl, it will appear that the roaring is pro- 

 duced in the act of inspiration, and not in that of expiration. If the horse is briskly 

 trotted on a level surface, and more partic\ilarly if he is liurried up hill, or if he is 

 suddenly threatened with a stick, this peculiar sound will be heard and cannot be 

 mistaken. When dishonest dealers are showing a horse that roars, but not to any 

 great degree, they trot away gently, and as soon as they are too far for the sound to 

 be heard, show off the best jiaces of the animal ; on returninsr, they gradually slacken 

 their speed when they come within a suspicious distance. This is sometimes techni* 

 cally called " the dealers' long trot." 



Roaring is exceedingly unpleasant to the rider, and it is manifest unsoundness. It 

 is the sudden and violent rushing of the air through a tube of diminished calibre; 

 and if the impe<liment, whatever it is, renders it so difficult for the air to pass in some- 

 what increased action, sufficient cannot be admitted to give an adequate supply of 

 arterialized blood in extraordinary or long-continued exertion. Therefore, as impair 

 ing the function of respiration, although, sometimes, only on extraordinary occasions 

 it is unsoundness. In as many cases as otherwise, it is a very serious cause of un- 

 soundness. The roarer, when hardly pressed, is often blown even to the hazard of 

 suflfocation, and there are cases on record of his suddenly dropping and dying when 

 urged to the top of his speed. 



It must not, however, be taken for granted that the roarer is always worthless. 

 There are few hunts in which there is not one of these horses, who acquits himself 

 yery fairly in the field ; and it has occasionally so happened that the roarer has been 



