296 1HE FARM DOCTOR. 



modified, their numbers are multiplied, and they become sur- 

 rounded by an excess of semi-fluid matter (lymph), with, it may 

 be, one of the following results : — \st. The softening of the 

 bone and the removal of its earthy salts, until it can be cut 

 with a knife or gives way under the weight of the animal ; 2^, 

 the transformation of the lymph into pus on the surface of the 

 bone or in its interior, where it may remain imprisoned for 

 an indefinite length of time; 3</, the hardening of a limited 

 amount of lymph in the cells or inter-spaces of the bone, com- 

 pressing the blood-vessels, limiting the supply of blood, and 

 favouring ulceration or even death of the part ; A,th, from the 

 above cause, or from a perversion of the plastic or assimilating 

 powers of the nuclei, ulceration sets in on the surface or in the 

 interior of the bone, and the bony matter is steadily removed 

 to be replaced by an irregular excavation or a cavity filled by a 

 bloody ichor; 5//;, the swelling may completely close the 

 blood-vessels of the bone, or the inflammation may cause 

 coagulation of the blood within them throughout a considerable 

 portion, which accordingly dies, and has to be removed as a 

 foreign body ; 6///, short of those extreme conditions and more 

 commonly, the exudation leads to a partial softening and 

 general swelling of the inflamed part, and this becoming con- 

 solidated and hardened there is a material increase of size; 

 7M, and by far the most frequently, the inflammation affects 

 the superficial layer of bone and its investing fibrous membrane, 

 and the exudation, taking place between these, is soon consoli- 

 dated into a layer or tumour of bone on the surface ; 8///, any 

 exudation on the outer side of the fibrous covering is also liable 

 to be calcified and to form hard tumours, but these do not 

 acquire the true bony texture like that formed between *he 

 membrane and the bone. 



General Symptoms. — In the slightest forms of inflammation 

 there may be little or no lameness, though usually there is a 

 halt on the affected limb when trotted on a hard surface. The 



