GOLD MEDAL PRIZE ESSAY, 1880 . 
219 
With regard to the height of the mean trajectory, in order to obtain 
an increase rather than a decrease in the angle of drop of the bullets, 
as well as to avoid losing the greater number of the latter in the 
parapet, the lower half of the cone should be made use of—that is, the 
mean trajectory must pass above the crest and, in order that the cone 
may reach the latter, within a distance equal to the radius of the cone 
at that part. Bearing in mind what has already been said on the 
subject, it seems best to make a compromise between length of spread 
along the crest and loss in bullets and in angle of drop and to fix the 
height of the mean trajectory at one-fourth the diameter of the cone 
over the crest, as shown in Fig. 8.* 
But with such—as we believe the best—application of shrapnel, can 
the entrenchment be considered sufficiently searched out ? Certainly 
not; for the lowest bullet would pass over the head of a man 6 ft. high, 
standing in the trench—in fact, but men actually firing could be 
touched, and to protect these a bonnette with loopholes could readily 
be formed of sand-bags, &c., against which shrapnel would be power¬ 
less and which would have the further advantage of increasing the 
shelter in rear.f 
Would, now, common shell, though not the natural projectile, so to 
speak, avail any better than shrapnel for searching ? From the great 
spread of its splinters it doubtless would, providing only it could be 
burst about the crest, otherwise, due to the small number of fragments 
and their irregular dispersion, the effect would be insignificant. 
Would it, then, be practically possible to obtain a sufficiently regular 
burst about the crest to be effective, using either time or percussion 
fuze? We think not: for if the latter fuze was used, only shells 
striking within about a yard of the crest, or on the bonnette, if there 
was one, would be effective—in fact, the mean trajectory should pass 
through the crest, as in Fig. 8; all others would either be lost in the 
parapet, or, clearing it, would drop too much to the rear to have any 
immediate effect; and if time fuze was used there would be even less 
chance of result, for the fuze, as before mentioned, does not admit of 
nice adjustment to distance and therefore it might be impossible to hit 
off the burst within the narrow limits necessary for effect. 
Against the breastwork the effective power of field projectiles there¬ 
fore stands thus; shrapnel has no real searching power, not even 
against defenders actually firing, if the latter are protected by a 
bonnette, but it covers the ground at some distance to the rear well; 
common shell may have an imperfect searching effect, but with wasteful 
expenditure of ammunition; it will, however, destroy the bonnette and 
reduce the crest. 
* The mean trajectory thus passes 2 , 35ft., approximately, above the crest, the point of burst 
being 7 ft. 6 ins. above the plane of the latter. 
The Prussian “Artillery Drill Regulations” lay down that shrapnel should be burst 7 ft. to 10ft. 
above the crest ; which, for the distance of burst and angle of descent we have taken, would give the 
mean trajectory passing from 1 to 4 ft. above the crest. 
f Increasing the range would, of course, increase the angle of descent of projectile and bullets, 
but such increase would not be sufficient to counterbalance consequent disadvantages—as loss of 
velocity, facility of observation, &c. 
