224 Means of measuring the initial Felocittj 



. The mean velocity deduced from the ten preceding expe- 

 riments is 390-4 7 metres, nearly the same which results 

 from the whole of the experiments. The mean value found 

 for the velocity per second of balls thrown from the infantry 

 musket was 428 metres, the ratio of which to the preceding 

 is as 1 1 to 10. These experiments seem to indicate that the 

 infantry musket might be shortened without much lessening 

 its rana;e ; but besides that the commissioners had no inten- 

 tion of deducing from these first trials any conclusions ap- 

 plicable to artillery, it is proper to observe, that some mili- 

 tary considerations, besides those of range, are in favour of 

 lensth in an infantry musket. 



If we wished to select from the accurate experiments hi- 

 therto published in regard to the projectiles of artillery some 

 proper for being nearly an object of comparison with those 

 mentioned above, we might take from the work of doctor 

 Hutton those which he made with a cannon of the smallest 

 dimensions, and which he marks No. 1, the bore of it 

 being 7 decimetres in length and about 51 millimetres in 

 diameter. The general results consigned to a table formed 

 from the whole of the experiments, give for the case, when 

 the weight of the charge of powder is, as above, one-half 

 that of the bullet, an initial velocity of 435 metres per se- 

 cond, which differs very little from the velocity found with 

 the infantry musket. Dr. Hutton's pieces numbered 2, 3, 

 and 4, and which were longer, gave mean velocities more 

 considerable. 



The commissioners made some trials with half charges, 

 that is to say, expelled the ball with the fourth part of its 

 weight of powder : the mean value of the velocity of the 

 ball thus projected was found for the infantry musket to be 

 234 metres, and for the musketoon 252. These two velo- 

 cities are sensibly equal, and exceed the halves 214 and 193 

 of those given by whole charges. 



There is reason to presume that these circumstances de- 

 pend chiefly on the complete inflammation of the powder 

 w hich takes place when there is only half a charge. 



in the last place, the coinmissioncrs, to multiply their 

 trials on the application of colonel Grobert's apparatus to 

 horizontal firing, wished to obtain some data in regard to 

 the resistance offered by the air to the motion of the ball, 

 the diameter of which was 15 or 16 millimetres. The 

 mouth of the barrel, which was first at the distance of 2'35 

 metres from the first fixed screen, was removed to that of 

 18"44 metres, by means of which its distance from the first 

 fixed screen was 20*79 metres. In this position the velocity 

 I with 



