ver. Now if the weight of the body is small in comparison to that of the balls, etc., as is the case in properly constructed shrapnel, the value of V may become quite large in proportion to V, which is always small in high angle firing. Therefore the reduction of the remaining velocity in the body of the shrapnel caused by the bursting charge may be very great, in fact it may entirely overcome that velocity and the body of the shrapnel receive a motion to the rear. In this way may be explained all the observed phenomena cited in this treatise; only the body of the shrapnel was confused with the whole shrapnel by the obserThe parts which fly forward do not form a single mass, and therefore are not seen by the observer; but they always receive an increase in velocity whenever the bursting charge is placed in rear of the balls. That a force in the projectile can destroy the work stored up in it by means of the charge in the gun, or can change it in ever so slight a degree, is contrary to all laws of mechanics. Moreover, the fact that a shrapnel held firmly in position by an abutment will, if exploded, give greater velocity to the balls through the bursting charge, than one exploded when hanging free, is also in full accord with what has already been said; to the weight of the body of the projectile is added the weight of the abutment which may be assumed infinitely great, and the bursting charge, which in the case of the suspended shrapnel performs work on both the body and the balls, in this case performs no work on the body of the shell. The total work of the bursting charge being approximately the same in both cases, the balls will therefore receive a greater velocity. On page 339 there is a view expressed which ought not to go uncontradicted, especially since it is very widely disseminated. that the firing at covered targets by torpedo shells out of straight trajectory guns requires fuzes of unheard of accuracy. This is a view which has grown up only on target ranges which are not fixed according to war conditions, but fitted up for the particular object in view, and where observations are made at the targets. Now, where the position of the mean bursting point can be regulated entirely at will, a small scattering of the balls is naturally very desirable. But the case is entirely different in actual battle, where the observations are unreliable, and where, even if observation were reliable, no fine corrections could be made. In this case the smallest error in the location of the mean bursting point would entirely ruin the firing, if the scattering of the balls was very small; whereas, by the scattering of the balls some effective charges, if they have a cone angle of from 80° to 90° and the cone angle is less hollow than in the present torpedo shell. b. A field howitzer with projectiles which have a wide opening of cone angle of from 60° to 70°, like those proposed in the foregoing article. C. If neither of these two means bring about a substantial increase of efficiency, there remains the method adopted by the French, their walled torpedo shells with very large charges, perhaps the last resort. Dependence is placed in this case, not on the work of the fragments but on the atmospheric pressure due to detonation of the projectile. It is a desperate means and it can therefore be easily understood that no other country has adopted it. (See Revue d'Artillerie, February, 1896). All these ways should be simultaneously introduced, according to my opinion, so that without loss of time, the means accomplishing the greatest result could be ascertained. Now only a few details, which only slightly touch upon the main question but which are of sufficient importance to be elucidated, so that false conclusions will not be drawn from the above discussion. In my opinion the bursting of the shrapnel is not properly described in the foregoing. On page 167 it is stated that the gas produced by the burning of the bursting charge exerts a pressure on the base of the projectile which results in a retardation of motion of the whole projectile. This is entirely impossible and is caused by an easily comprehended optical illusion. The gases not only exert a pressure on the base of the projectile but also on the diaphragm and through. this on the contained balls. By means of this pressure the body of the shrapnel, in case this remains whole, receives a velocity to the rear, while the balls have received a similar one to the front. The velocity imparted depends on the work performed by the bursting charge and the weight of the mass moved. The relations are similar to those which exist when a gun is fired, the projectile goes in one direction and the gun in the opposite direction. F Representing the weight of the body by B, that of the balls, diaphragm and point together by F, and by V and V, their respective velocities, then the products of the two masses and their velocities must be equal, or, BV1 = FV,. If the projectile has at the bursting point the velocity V, after the burst the body will have the velocity VV, and the balls V + V‚. ver. Now if the weight of the body is small in comparison to that of the balls, etc., as is the case in properly constructed shrapnel, the value of V may become quite large in proportion to V, which is always small in high angle firing. Therefore the reduction. of the remaining velocity in the body of the shrapnel caused by the bursting charge may be very great, in fact it may entirely overcome that velocity and the body of the shrapnel receive a motion to the rear. In this way may be explained all the observed phenomena cited in this treatise; only the body of the shrapnel was confused with the whole shrapnel by the obserThe parts which fly forward do not form a single mass, and therefore are not seen by the observer; but they always receive an increase in velocity whenever the bursting charge is placed in rear of the balls. That a force in the projectile can destroy the work stored up in it by means of the charge in the gun, or can change it in ever so slight a degree, is contrary to all laws of mechanics. Moreover, the fact that a shrapnel held firmly in position by an abutment will, if exploded, give greater velocity to the balls through the bursting charge, than one exploded when hanging free, is also in full accord with what has already been said; to the weight of the body of the projectile is added the weight of the abutment which may be assumed infinitely great, and the bursting charge, which in the case of the suspended shrapnel performs work on both the body and the balls, in this case performs no work on the body of the shell. The total work of the bursting charge being approximately the same in both cases, the balls will therefore receive a greater velocity. On page 339 there is a view expressed which ought not to go uncontradicted, especially since it is very widely disseminated. that the firing at covered targets by torpedo shells out of straight trajectory guns requires fuzes of unheard of accuracy. This is a view which has grown up only on target ranges which are not fixed according to war conditions, but fitted up for the particular object in view, and where observations are made at the targets. Now, where the position of the mean bursting point can be regulated entirely at will, a small scattering of the balls is naturally very desirable. But the case is entirely different in actual battle, where the observations are unreliable, and where, even if observation were reliable, no fine corrections could be made. In this case the smallest error in the location of the mean bursting point would entirely ruin the firing, if the scattering of the balls was very small; whereas, by the scattering of the balls some effective shots would be obtained even though the position of mean bursting point was not absolutely favorable. The great accuracy of the gun does not always guarantee the greatest probability of hitting. So that one can almost say the scattering of the fuze is much too small, since it is well known that the firing rules require that the firing shall be conducted at three ranges differing by 50 m. Of course in this way the scattering in depth only is affected, in width it would remain the same. Notwithstanding the fact that my views differ from those of the author of the above discussion in many points, I am of the opinion that in publishing it, he has done a valuable service toward the development of this important question. I believe that the proposition to provide shrapnel with chambers both in the base and point, is especially worthy of attention. ROHNE, Major General, Commander of the 8th Field Artillery Brigade. [Translated by First Lieutenant E. S. BENTON, 1st Artillery]. |