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wliicli it is a symptom, and then cure tlie disease if possible, and the 

 cough will cease. 



The treatment of the affections will be found under their appro- 

 priate heads, to which the reader is referred. 



PLEURODYNIA. 



This is a form of rheumatism that affects the intercostal muscles, 

 that is, the muscles between the ribs. The apparent symptoms are 

 very similar to those of pleurisy. The animal is stiff and not inclined 

 to turn around; the ribs are kept in a fixed state as much as possible. 

 If the head is pulled round suddenly, or the affected side struck with 

 the hand, or if the spaces between the ribs are pressed with the fingers 

 the animal will flinch and perhaps emit a grunt or groan expressive 

 of much pain. It is distinguished from pleurisy by the absence of 

 fever, cough, the friction-sound, the effusion into the chest, and by 

 the existence of rheumatism in other parts. The treatment for this 

 affection is the same as for rheumatism affecting other parts. 



WOUNDS PENETRATING THE AVALLS OF THE CHEST. 



According to the theory of some teachers of phj'-siology, Avhen an 

 opening is made in the wall of the chest sufficient for the admission 

 of air a collapse of the lung should occur. But in practice this is not 

 always found to be the case. The writer has attended several such 

 cases, and one in particular was not seen until about twelve hours 

 after the wound was inflicted. It is true the breathing was consider- 

 ably altered, but no bad effect followed the admission of air into the 

 thoracic cavity. The wound was closed and treated according to the 

 method of treating wounds generally, and a speedy and perfect recov- 

 ery was made. The Avound may not penetrate the pleura; in such 

 cases no great harm is done, but if the pleura is penetrated pleurisy 

 may follow, and even pneumonia if the wound involves the lung. 



The condition called pneumo-thorax means air in the chest. This 

 may be due to a wound in the wall of the chest, or it may be due to a 

 broken rib, the sharp edge of which wounds the lung sufficiently to 

 allow air to escape into the space between the lung and ribs, which is 

 naturally a vacuum. Air gaining access to the thoracic cavity through 

 a wound may have a peculiar effect. The wound may be so made that 

 when the walls of the chest are dilating a little air is sucked in, but 

 during the contraction of the wall the contained air presses against 

 the torn part in such a manner as to entirely close the wound ; thus a 

 small quantity of air gains access with each inspiration, while none is 

 allowed to escape until the lung is pressed into a very small compass 

 and forced into the anterior part of the chest. The same thing may 

 occur from a broken rib inflicting a wound in the lung. In this form 

 the air gains access from the lung, and there may not even be an open- 

 ing in the walls of the chest. Decomposition of the fluid in hydro- 

 thorax, with consequent generation of gases, is said to have caused 



