1 62 Experiments to determine 



it, when fired against it from the distance of six feet, 

 the same ball, discharged from the same pistol, with the 

 same charge of powder, may be made to pass quite 

 through one deal board, and bury itself in a second 

 placed behind it, merely by preventing the loss of force which 

 arises from what is called windage ; as I have found more 

 than once by actual experiment. 



I have, in my possession, a musket, from which, with 

 a common musket charge of powder, I fire two bullets 

 at once with the same velocity that a single bullet is dis- 

 charged from a musket on the common construction, 

 with the same quantity of powder. And, what renders 

 the experiment still more striking, the diameter of 

 the bore of my musket is exactly the same as that of a 

 common musket, except only in that part of it where it 

 joins the chamber, in which part it is just so much con- 

 tracted that the bullet which is next to the powder may 

 stick fast in it. I ought to add that, though the bullets 

 are of the common size, and are consequently consider- 

 ably less in diameter than the bore, means are used 

 which effectually prevent the loss of force by windage ; 

 and to this last circumstance it is doubtless owing, in a 

 great measure, that the charge appears to exert so great 

 a force in propelling the bullets. 



That the conical form of the lower part of the bore, 

 where it unites with the chamber, has a considerable 

 share in producing this extraordinary effect, is however 

 very certain, as I have found by experiments made with 

 a view merely to ascertain that fact. 



I will finish this paper by a computation, which will 

 shew that the force of the elastic fluid generated in the 

 combustion of gunpowder, enormous as it is, may be 

 satisfactorily accounted for upon the supposition that its 



