$6 THE DISEASES OF THE HORSE. 



are fetid. Arsenic occasionally relieves inflation. Careful 

 dietary ; nutritive, oleaginous food. Linseed oil. Iron 

 and other tonics promote convalescence. 

 For doses, see pages 13 to 29. 



PLEURISY (PLEURITIS), 



Is inflammation of the pleura — a membrane investing 

 the organs of the chest. When the inflammation extends 

 to the lungs, the disease is called pleuro-pneumonia. The 

 secretions of the pleura are usually water}-, with or with- 

 out lymph. The water is usually of a clear, bright yel- 

 low color, closely resembling the serum of the blood, 

 though in some cases it is rendered turbid by the lymph 

 floating in it. In others it is red from being tinged with 

 blood. In others still it is of a sort of milky or whey 

 color, and fetid from being mixed with pus. The 'lymph 

 consists of masses of gelatinous or albuminous matter, 

 hanging about the chest in shreds " after the fashion of 

 a cobweb," and sometimes forming what are called adhe- 

 sions or false membranes. It sometimes walls the water 

 in as it were, confining it like pus within an abscess. It 

 at first probably gives rise to more or less pain, as it in- 

 terferes with the free action of the lungs, but the parts 

 evidently soon become adjusted to each other. Pus some- 

 times accompanies acute as well chronic pleurisy, and in 

 some cases gangrene and even abscess of the side super- 

 vene. In chronic cases the pleura becomes thickened and 

 tough, apparently less vascular, and assumes a morbidly 

 white aspect. Sometimes it is studded with tubercle-like 

 knots. Pleurisy of one side is rare ; but the opposite 

 side often takes the disease from sympathy. 



The disease has a dangerous tendency. It usually comes 

 and goes suddenly. Death is also sudden — a few hours. 

 The chronic form is slow and comparatively painless. It 

 may last for weeks. It may follow or be independent of 

 the acute form. The disease is peculiar to four and five- 



