228 OPEEATIONS ON BONES. 



wMcli forms a species of cement by which the different constit- 

 uents are blended into a consistent mass to be spread upon the 

 surface covering the locality of the fracture. Its components are 

 black pitch, resin, and Venice turpentine, blended by heat. The 

 dressing may be applied directly to the skin, or a covering of thin 

 Unen may be interposed. A putty made with powdered chalk 

 and the white of an egg is recommended for small animals, though 

 a mixture of sugar of lead and burnt alum with the albumen is 

 preferred by others. Another formula is spirits of camphor, 

 Goulard's extract and albumen. Another recommendation is to 

 saturate the oakum and bandages with an adhesive solution formed 

 with gum arable, dextrine, flour paste, or starch. This is advised 

 particularly for small animals. Dextrine mixed, while warm, with 

 burnt alum and alcohol cools and solidifies into a stony consistency, 

 and is preferable to plaster of Paris, which is less friable and has 

 less solidity, besides being heavier and requiring constant additions 

 as it becomes older. Starch and plaster of Paris form another 

 good compound. 



In applying the dressing the leg is usually padded with a 

 cushion of oakum, thick and soft enough to equalize the irregu- 

 larities of the surface and to form a bedding for the protection of 

 the skin from chafing. Over this the splints are placed. The 

 material for these is, variously, pasteboard, thin wood, bark, laths, 

 gutta percha, strips of thin metal, as tin or perhaps sheet iron. 

 These should be of sufficient length not only to cover the region 

 of the fracture, but to extend sufficiently above and below to 

 render the immobUity more complete than in the surroimding 

 joints. The splints agaia, are covered with cloth bandages, linen 

 preferably, soaked in a glutinous moisture. These bandages are 

 to be carefully applied, with a perfect condition of lightness. 

 They are usually made to embrace the entire length of the leg, in 

 order to avoid the possibility of iaterference with the circulation 

 of the extremity, as well as for the prevention of chafing. They 

 should be rolled from the lower part of the leg upward, and 

 carefully secured against loosening. In some instances suspen- 

 sory bandages are recommended, but excepting for small animals 

 our experience does not justify a concurrence in the recommen- 

 dation. 



These permanent dressings always need careful watching in 

 reference to their immediate effect upon the region they cover, 



