126 



judgment of the i3ersoii directing tlio treatment of the case. If it is 

 seen that any one thing is doing harm, then that particular thing 

 shonkl be omitted. For instance, if drenching the animal is attended 

 with harm, that is, if it nnnecessarily excites him, or if he obstinately 

 refuses to swallow the medicine, then do not further annoy him by 

 persistently trying to do what you are able to see only makes matters 

 worse. Omit the drenching, and dissolve 3 drams of bicarbonate of 

 potassium in every bucketful of water he will drink of his own free 

 will. Give the quinine in capsules or balls, and also the carbonate 

 of ammonia balls. A balling iron (or mouth speculum) may be 

 obtained from any veterinar}^ instrument dealer. A little practice 

 with it will enable joxi to become somewhat expert in giving medi- 

 cines in the latter form. Do not give quinine and ammonia together; 

 let at least an hour intervene between the administration of the two 

 different medicines. 



PLEURISY. 



The thoracic cavity is divided into two lateral compartments, each 

 containing one lung, besides other organs. Each lung has its sepa- 

 rate pleural membrane or covering. The anatomical arrangement of 

 the i^leura is simple to the anatomist, but a detailed description of it 

 would be bej' ond the comprehension of the average reader. Suffice it 

 to say that the i)lenra is the thin, glistening membrane that covers 

 the lung, and also completely covers the internal walls of the chest. 

 It is very thin, and to tlie ordinar}^ observer appears to be x^art of the 

 lung, which, in fact, it is for all practical purposes. The smooth, 

 shiny surface of the lung, as well as the smooth, shin}^ surface so 

 familiar on tlie rib, is the pleura. In health this surface is always 

 moist. A fluid (called serum) is thrown off (secreted) by the pleura, 

 which causes the surface to be constantl}' moist. This is to prevent 

 the effects of friction between the lungs and the walls of the chest and 

 other contiguous i^arts which come in contact. It must be remem- 

 bered the lungs are constant!}' dilating each time a breath is taken in, 

 and contracting each time a breatli of air is expelled. It maj^ be 

 readily seen that if it were not for the moistened state of the surface 

 of the pleura the continual dilation and contraction and the conse- 

 quent rubbing of the iDarts against each other would cause a serious 

 friction. This, then, is the office of the pleura — to secrete or moisten 

 its surface with a fluid to prevent the ill effects of friction. 



Inflammation of this membrane is called pleui'isy. Being so closely 

 united Avith the lung, it can not always escape participation in the 

 disease when the latter is inflamed. Pleurisy may be due to the same 

 predisposing and exciting causes as mentioned in the beginning of this 

 work as general causes for diseases of the organs of respiration, such 

 as exposure to sudden changes of temperature, confinement in damp 

 stables, etc. It may be caused by wounds that penetrate the chest, for 



