OP THE BONES. 391 



% 



which is produced by fire-arms, is accompanied, in its union, 

 by a large and permanent osseous production. It is in this 

 production especially, in the same manner as in exostosis, as 

 well as in reproduction after necrosis, that a great mass of new 

 osseous matter may be seen. After being fluid it becomes solid, 

 soft, flexible, and elastic, so that it might almost be mistaken 

 for cartilage. But this substance contains numerous bony 

 points; and if the observation is made in an animal that has 

 taken madder, it is found to be of a rose colour, or even red, 

 which is never the case with cartilages. It afterwards becomes 

 hard like a common bone, and even more so. This permanent 

 bony tumour bears the name of callus. 



611. Wounds of the bones differ from fractures, in the 

 state of the solution of continuity itself, and in its mode of 

 reparation, which is different from that described above. The 

 bony tissue being very hard, and possessed of little flexibility, 

 a sharp instrument which cuts it obliquely really produces a 

 multitude of small fractures in the fragment which it raises, 

 just as happens to a chip of dry wood raised by the blow of a 

 hatchet As to the subsequent union of this cut, as that of a 

 fracture with wound, it commonly does not take place until 

 after an exfoliation, and by the formation of suppurating granu- 

 lations. 



612. The loss of substance of the long bones, in young and 

 healthy subjects, is followed by a more or less extensive, and 

 sometimes complete reparation or production. In birds,* the 

 periosteum may even be removed, together with a large por- 

 tion of one of the bones of the fore-arm, and these parts are in 

 time reproduced by a kind of vegetation of the t\vo ends. In 

 the human species, when the loss of substance of a bony cylin- 

 der is inconsiderable, and the disposition of the parts does not 

 admit of the fragments being brought together, there is pro- 

 duced, by the sinking and elongation of the ends, a cartilagini- 

 form fibrous substance, which does not acquire the hardness 

 of bone in its whole extent. 



These more or Jess advantageous results of the reproduction 



* Charmeil. Op. Cit. 

 . 51 



