GUN-SHOT WOUNDS. 459 



SPENT BALLS. 



However near to the end of its career a cannon ball may 

 be, it is still a most dangerous thing, and many a leg has been 

 knocked off by a ball whose progress seemed as slow as that of 

 a cricket ball. But the most important series of injuries caused 

 by spent balls are the contusions which they inflict by striking 

 against and rolling over parts after they have lost the velocity 

 required for penetrating or carrying them away. Such injuries 

 were formerly called wind contusions, being supposed to depend 

 on the commotion of the air caused by the passage cf a ball 

 close to the part injured without striking it; but now it is 

 known tlmt the wind of a hall, though startling enough, has no 

 bad consequences. In many instances, although the skin may 

 be intact or but trivially grazed, still the parts beneath have 

 been irretrievably disorganized, the muscles pulpified, the bones 

 comminuted, and large vessels and nerves torn across. In less 

 severe cases there may be enormous extravasations, with or 

 without fracture of bone, followed by profuse and unhealthy 

 suppuration and sloughing of the injured parts. 



MUSKET-SHOT. 



\Ylien a musket or pistol ball has penetrated the body, there 

 is seen a hole, perhaps rather smaller than the ball itself, with 

 its edge inverted; and if the ball has passed completely through, 

 there will be a larger and more ragged orifice, with its edge 

 everted. The oscillations of a musket ball are shown to be in 

 the inverse ratio of its velocity, by its effects on bones. Thus, 

 Avhen a ball propelled with great velocity strikes against a bone 

 of compact tissue, such as the body of the femur, it produces a 

 comminuted fracture of the worst kind, shivering the bone into 

 splinters, and often splitting it up to a great distance. But 

 when the velocity of the ball is very slight, it may be flattened 

 and rebound ; or may, if it strike a sharp edge, such as the spine 

 of the tibia, be itself split into pieces. If it strike the can- 

 cellated tissue, it will probably bore a canal through it, of which 

 the exit may possibly be twice as large as the entrance. If the 

 propelling force be nearly exhausted, the ball may lodge in the 

 cancellous tissue, forming for itself a kind of chamber, from 



