56 Experiments upon Gimpowder. 



In the nth, 12th, 13th, and r4th experiments, when 

 the piece was fired with 310 grains of powder and a bul- 

 let, the recoil was 24.69, 24.95, 24.9, and 24.9 : and in 

 the 15th, 1 6th, 1 8th, and 19th experiments, with 330 

 grains of powder, the recoil was 26.2, 26.2, 26.3, and 

 26.4. The regularity of these numbers is very striking; 

 and though we cannot compare the velocities of the bul- 

 lets determined by the two methods, as we have done in 

 other cases (as there are reasons to believe that the veloci- 

 ties, as they are set down in the tables, are not much to 

 be depended on, and as the recoil, with the given charge 

 of 3 10 grains of powder, without a bullet, is not known), 

 yet the regularity of the recoil in these experiments 

 affords good grounds to conclude that the method of 

 determining the velocities of bullets founded upon it 

 must be very accurate. 



But of all the experiments those numbered from 84 

 to 92, inclusive, afford the strongest proof of the accu- 

 racy of this method. In those, every possible precau- 

 tion was taken to prevent errors arising from adventitious 

 circumstances ; and the weights of the bullets and their 

 velocities were so various that the uniform agreement 

 of the two methods of determining the velocities, in 

 those trials, amounts almost to a demonstration of the 

 truth of the principles upon which this new method is 

 founded. 



By the following table the result of these experiments 

 may be seen at one view. 



