TlSEASES OF RESPIRATORY PASSAGES AND ORGANS. 119 



ai-e unfolded to us in the various departments of her great domain. 

 We. must altogether abandon a blind faith in doses of poisDnoua 

 medicines and bleedings; otherwise, all our eiforts are as but a 

 withering simoom. For example, over seventy thousand head of 

 cattle have lately perished of what has been called the " rinder- 

 pest/' in and around the great city of London, which is claimed 

 to be the model seat of veterinary learning for all British sub- 

 jects It is probable that the heroic practice there taught haa 

 something to do with this tremendous mortality; for we learn 

 that a more simple plan of treatment has been inaugurated bj 

 another class of physicians, whose medicines are almost inert, anc^ 

 they have been more successful than the advocates of setons, blio 

 ters, sedatives, and narcotics, not forgetting their " sheet-anchor," 

 calomel — as Napoleon observed, in derision, when on the islam 

 of St. Helena, " Bleeding and calomel for ever ! " Simple, sana- 

 tive medicines act potently, yet silently, after the fashion of 

 Nature's workings; so that we should never attempt to force hvi 

 to adopt o'T system of cure for that of her own. 



Pleurisy. 



Pleurisy signifies inflammation of the pleura. This membrane 

 lines the internal surface of the chest, and furnishes a covering 

 to the organs within the chest. It also serves to divide the 

 chest into two cavities, which are known as the right and left. 

 This membrane is similar in its texture and function to that 

 which lines the cavity of the abdomen. Both are serous mem- 

 branes, secreting, on their inner s'' /face, a lubricating fluid, which 

 guards against friction. This membrane is the seat of pleurisy, 

 and pleurisy consists of inflammation of it. 



Causes. — It may be presumed that the ordinary causes which 

 produce affections of the lungs are operative in the production 

 of this malady, viz.: exposure, by which the surface of the body 

 becomes chilled; injuries in the thoracic region; over-work; an 

 impure atmosphere ; a plethoric state of the system ; in snort, 

 &r.y cause which is likely to produce an inflammatory affection 

 in other parts of the body. I have known horses become the 

 subjects of this malady that have been confined to the stable 

 for weeks. Such cases are clearly traceable to plethora, want of 

 exercise, and impure air. It is possible that some animals inherit 



