LATERAL FACES OF THE BODY. 157 



h. Those which have been affected with a serious pneumonia or a pleurisy, 

 and to which repeated applications of revulsives and blisters have been made, 

 often show along the inferior surface of the region denudations accompanied by 

 large discolorations of the skin or the hairs. It is important, in examining such 

 animals, to observe attentively the character of the cough and the movements 

 of the flank, in order to be assured that these affections no longer exist. 



c. At other times there are cicatrices situated at the level and in front of 

 parts covered by the saddle, and due to setons inserted for a therapeutic pur- 

 pose. These counter-irritants are directed vertically, or are slightly oblique from 

 before backward and from above to below. When they are observed, or their 

 traces are found, we should infoi-m ourselves more completely as to the reasons 

 for tlieir application, and the present condition of the horse, according to the 

 juanner indicated below. 



d. Heavy draught-, light draught-, and saddle-horses offer also, on the parts 

 "which receive pressure and friction from the shafts, the pole, the traces, the saddle, 

 and the girth, dejtilations, wounds, cicatrices, and sit-fasts, known under the name 

 of corm, which are the result of wounds occasioned by these pieces of the 

 harness. 



e. Finally, bony tumors may be seen upon the course of one or several of the 

 ribs. These are traces of old fractures, usually situated upon the middle parts of 

 •the region. Nearly always they are complicated by contracting adhesions with 

 the lung, through the existence of a localized inflammation of the pleura which 

 •covers the internal surface of these bones. Likewise, as Lecoq says, we have 

 reason to fear, especially when several ribs have been fractured, that a super- 

 vening affection of the chest may be aggravated by this cause. 



The Chest in General. 



We have now examined separately the regions which concur to 

 form this vast cavity, and we shall next investigate it as a whole with 

 regard to the correlation between its dimensions and its beatities. 



Definition ; Limits ; Anatomical Base ; Usages. — Tlie chest is that 

 part of the body which corresjxjnds to the Ijony cage designated under the name 

 of tliorax. Bounded above by the withers and the back ; in front by the neck and 

 the breast ; on each side by the shoulder, the arm, the axilla, and the ribs ; below 

 by the inter-axilla, the xiphoid region, and the abdomen ; and, finally, behind by 

 the abdomen and the flanks, it has for its osseous base the following parts: 



a. On the median line and above, the bodies of all the dorsal vertebrae. 



b. Laterally, the ribs and the intercostal spaces. 



c. Inferiorly, the superior face of the sternum and the cartilages of prolonga- 

 tion of the ribs. 



d. Behind, the diaphragm, convex in front and pierced by three openings, 

 traversed by the aorta, the oesophagus, and the posterior vena cava. 



Open in front to afford passage to the trachea, the oesophagus, and the vessels 

 of the head and anterior members, as well as to the important nerves, it has in 

 general the form of a cone, with the base posterior and truncated obliquely from 

 above to below, and from behind to before ; it is depressed upon its lateral faces. 



Its functions are complex and of three kinds : 



