188 ^ NON-INFLAMMATORY DISEASES OF BONES. 



use from the pain produced whenever any movement was at- 

 tempted to be made. But in these structures I did not detect 

 the slightest traces of fatty degeneration. The fat generally had 

 a mottled, watery appearance, which is very common in animals 

 that are rapidly losing flesh, and this had been the case in a very 

 marked degree for a short time before the horse was destroyed. 

 In disarticulating the limbs from the trunk, and also the several 

 bones of each limb one from the other, the appearance of the 

 interior of each joint was remarkable. In most instances, 

 although not in all, the articular cartilage was of a dark slate 

 colour, much thinner than is natural, and in many places it was 

 entirely lost. This was especially the case round the margin of 

 the articulations, leaving the bone at that part quite exposed. 

 The synovial membrane was considerably thickened, especially 

 in those parts where it is most vascular. The quantity of 

 synovia in each joint was small, of a dark colour, and in some 

 cases mixed with blood. The character of some of the articu- 

 lating surfaces, however, was quite different. In such, the arti- 

 cular cartilage was pale-coloured, and in some places of a 

 palish yellow, velvety to the feel, and evidently containing fat ; 

 thereby indicating that the cartilage cells had disappeared, and 

 fat had become deposited in their place. The ends of the bones 

 were so much softened, that by applying a slight degree of force 

 .to the capsular or articular ligaments, small portions of the bone 

 could easily be detached. The periosteal covering of the flat 

 and irregular, and also some parts of the long bones, was very 

 vascular, and could easily be stripped off. The bones generally 

 were likewise so very soft that they could be cut with a knife 

 in any direction with the greatest ease; and if pressure were 

 applied to the cut surfaces, or where the periosteum had been 

 removed, blood would ooze from numerous points. In the 

 interior of the bones the cancelli were filled with a red gelatin- 

 ous substance. The ribs, the vertebrse, and indeed all the irre- 

 gular and flat bones, were in the same condition. The shafts of 

 the long bones of the extremities were not visibly increased in 

 size, nor was the shell or compact structure much altered. The 

 ends of these bones, however, were enlarged and soft ; and on 

 making a section through them, in their long diameter, the 

 medullary canal, and especially the cancelli near to the extremi- 

 ties, had a singular, although not a uniform, appearance. In 



