288 DISEASES OF CATTLE. 



of the operator, but not alone in the selecting and use of the appliances; 

 for as much attention must be given to subsequent management. The 

 patients are unreasonable, and a single awkward motion may undo the 

 work of weeks so far as the union of the parts of the bone is concerned. 

 It takes place after the same process and, if the conditions are favor- 

 able, with greater rapidity than in the human being. The injury that 

 caused the fracture is almost sure to have extended to some of the 

 adjacent tissues, and even though the fracture may be of the simplest 

 type there is almost sure to be considerable hemorrhage around the 

 ends of the broken bone. This, however, is unimportant if the skin 

 remains intact, unless a very large vessel should be injured, or the 

 fracture should open some of the important cavities of the body, in 

 which case a fatal hemorrhage might result. If, on the other hand, the 

 fracture be a compound one, the external opening furnishes a fertile field 

 for the lodgment of disease-producing germs. Unless great care is exer- 

 cised in such cases a suppurative process is likely to be established 

 which will seriously interfere with if not entirely arrest the process of 

 union between the bones; or it may become so serious as to endanger 

 the general health of the animal and even be attended with fatal 

 results. This last danger is greater where the injury has occurred to 

 the bones of the arm or thigh. In such cases, owing to the dense cov- 

 ering of fascia which ensheathes the muscular coA T ering, pus is likely 

 to be imprisoned, and burrowing downward saturate the whole struc- 

 ture, not only endangering the limb, but, being likely to be reabsorbed,' 

 may set up blood-poisoning and seriously interfere with the general 

 health of the patient, even to causing death. In order as far as possi- 

 ble to prevent such an unfortunate complication the wound should be 

 carefully cleansed with a mild solution of carbolic acid, then dusted 

 over with iodoform before the bandages are applied, and cleansed and 

 dressed daily in the same way. After dressing always cover with 

 absorbent cotton. In the early process of union an exudation of lymph 

 takes place, which is at first fluid, gradually becoming thicker and 

 firmer tilUt forms a, callus in the shape of a ring or ferrule surround- 

 ing the detached portions of the bone, known as the external or 

 en sheathing callus. It occasionally happens that this callus only forms 

 at the ends of the bones, filling the spaces that exist between them, 

 when it is known as the intermediate callus. The process of union 

 may be divided into five stages: In the first stage, including the first 

 eight days, the detached portions of the bone and the sharp projections 

 that are not sufficiently nourished are absorbed; the blood which 

 escaped into the surrounding tissues, the result of the injury, is grad- 

 ually absorbed and the effused lymph which is ultimately to constitute 

 the temporary cartilage takes its place. In the second stage, from the 

 tenth to the twentieth day, the tumor or callus is formed and fibro- 

 cartilage is developed inside and around the exposed end of the bone. 

 In the third stage, extending from the twentieth to the fortieth or tif- 



