THE INFLUENCE OF AMMUNITION ON SHOOTING. 143 
those calculated by Bashforth’s abbreviated method. The abbreviated 
method assumes the trajectory to be a straight line. It only holds 
over short distances, or at high velocities, when the assumption is 
nearly true. The remaining velocity is of importance when we con- 
sider errors of times of burning of fuzes. The range table gives the 
remaining velocity at 2000 yards as 997 f.s. My calculation for the 
range table elevation and with the same muzzle velocity gives a 
remaining velocity of 947 f.s. For the purposes of this paper I prefer 
my results and use them in the comparisons which follow. 
(2) Huzes.—To simplify the consideration of fuzes we will assume 
that arrangements have been made to ensure regular shooting of the 
owder. 
a The range table gives the time of flight for 2000 yards as 5:2 secs. 
My calculation for the 1994 yards range is 4991 secs. Considering 
the calculated trajectory, and assuming we wish to burst our shell 80 
yards short of the target, the time of flight to this point is 4°738 secs., 
or say 4°74 secs., and our fuze would be set to burn for this time. The 
height above plane of the trajectory at this point is 19°34 feet. 
In the case of powder, I was able to point to a published specifi- 
cation. I regret to say I am unable to find one for fuzes. We shall 
surely, however, be well within the mark if, allowing for age and 
variation in manufacture, we say that a possible error of + 0°25 secs. 
may occur when our fuze is set to burn for 4°74 secs. 
If the fuze burns for 4°74 + +25 = 4:99 secs. the shell will practi- 
eally burst at the target. If the fuze burns for 4°74 — :25 = 4°49 
secs. the shell will burst 159 yards short of the target, and at a height 
above plane of some 38 feet. Neither of these shell could be con- 
sidered as satisfactory time shrapnel. 
In the case of a higher velocity gun these errors would be even more 
pronounced. 
A constant powder has been assumed in the foregoing. It does not 
require a vivid imagination to picture what pitiable results might 
follow if large errors were to creep in there. 
(3). Shell.—The next question is—how does weight of shell affect 
the shooting. 
For the purpose of this investigation I have taken a shell weighing | 
15:1 lbs. or rather over 15 lbs. 14 ozs. 
There are two separate points to be considered, viz: the effect on 
ranging and the effect on time shrapnel, of a difference in weight of 
the shell. This is necessary, because the times of flight and remaining 
velocities are not the same for shells of different weights which range 
the same distance. 
First, we must notice that the charge of powder which would impart 
a muzzle velocity of 1550 f.s. to a 15 Ib. shot will only impart a muzzle 
velocity of 1545 fis. to a 15:1 lb. shot. Firing then at the same 
elevation of 8° 12’, the 15: Ub. shot will range 1990°8 yards, as against 
the 1994 yards of the 15 Ib. shot; an error in range of 3-2 yards. 
The time of flight of the 15:1 1b. shot fired at this elevation ig 4°985 
secs., and its remaining velocity 948°6 f.s. It will be remembered 
