66 Experiments ^ipon Gunpowder. 



As this method of determining the velocities of the 

 bullets did not occur to me till after I had finished the 

 course of my experiments, and had taken down my ap- 

 paratus, I have not had an opportunity of ascertaining 

 the recoil with and without a bullet with that degree 

 of precision that I could wish. If I had thought of it 

 sooner, or if I had recollected that passage in Mr. 

 Robins's new Principles of Gunnery where he says, 

 " The part of the recoil arising from the expansion of 

 the powder alone is found to be no greater when it 

 impels a leaden bullet before it than when the same 

 quantity is fired without any wad to confine it," — I say, 

 if that passage had occurred to me before it had been 

 too late, I certainly should have taken some pains to 

 have ascertained the fact ; but as it is, I think enough 

 has been done to shew that there is the greatest proba- 

 bility that the velocities of bullets may, in all cases, be 

 determined by the recoil with great accuracy ; and I hope 

 soon to have it in my power to put the matter out of 

 all doubt, and to verify this new method by a course 

 of conclusive experiments, which I am preparing for 

 that purpose. 



In the mean time I would just observe, that if this 

 method should be found to answer when applied to 

 musket bullets, it cannot fail to answer equally well 

 when it is applied ^to cannon balls and bomb shells of 

 the largest dimensions ; and it is apprehended that it 

 will be much preferable to any method hitherto made 

 public ; not only as it may be applied indifferently to 

 all kinds of military projectiles, and that with very little 

 trouble and expence in making the experiment ; but also, 

 because by it the velocities with which bullets are actu- 

 ally projected ?iYQ determined ; whereas by the pendulum 



