72 
MINUTES OF PROCEEDINGS OF 
us no further information as to its actual accomplishment than a vague note, 
which states that “ Gruson's Works have since executed large orders for 
chilled shells with thin lead jackets for various Governments. - ” 1 
With respect to the form of the shot, the Palliser form was closely- 
observed and copied 3 —the length of head and its diameter at junction with 
the body being increased. In fact, the Gruson shot was made externally as 
like the Palliser as possible. Considering what an important influence the 
form has upon penetration, this, again, was not an unimportant departure 
from the original pattern. Before applying these alterations to the large 
gun, they were tried in an 8-inch (“72-pr.") Krupp gun, 3 which was 
present on the ground, and which during the trials played the useful part 
of a pioneer to the heavier weapon. 
On July 7, after a month's private experimenting, we find the Prussians 
prepared once more to enter the lists against the English gun, in which no 
change of any sort had been made during the interval. The effect of the 
various experiments and united alterations had been to give to the Krupp 
gun an initial velocity of from 1286 to 1414 ft. per second, according to 
whether a 336 lb. or 275 lb. shell was used; 4 and this velocity, according to 
Mr. Krupp, 5 gave a momentum to the Krupp projectiles of from 16*26 to 
16*78 metre-tons per centimetre of circumference, as against 12*35 metre- 
tons for the English shot. In other words, the Krupp resumed the contest 
with a theoretical ballistic superiority of from 30 to 33 per cent. 6 The 
Prussian official report also gives a superiority of momentum of about 33 per 
cent, to the Krupp. If other formulae and modes of calculation be adopted, 
the figures representing the relative ballistic powers of the two guns will vary. 
Thus, Captain von Doppelmair assigns a theoretical superiority of momentum 
to the Prussian gun of from 17 to 15 per cent., according to whether the 
heavy or light shell is used. 7 The theoretical superiority of penetrative 
power will depend upon the range and upon the value assigned to the lead 
jacket. The Prussian official report on these trials gives the Krupp gun a 
theoretical penetrative superiority 8 of from 29 to 21 per cent., if calculated 
by the English formula, and of from 25 to 17 J per cent, if calculated by 
the Prussian formula. Sir William Armstrong estimated it at about 18 per 
cent. 9 Without attempting to assign a precise figure to the theoretical 
1 Doppelmair, p. 49, note. 2 Ibid. pp. 19, 25. 3 Ibid. pp. 25, 26, 63. 
4 Ibid. pp. 28-63. 5 Krupp, Table III. 
6 In a later pamphlet, Mr. Krupp estimates the ballistic power of his 9|-inch guns at from 
15 to 34 per cent, superior to that of the English 9-inch gun, according to whether the Krupp 
guns are of 14,000 or 15,500 kilos. See “ Canons de Marine et des Cotes,” Tables I., IV. 
7 Doppelmair, p. 30. 8 Range not stated. 
9 Captain W. H. Noble, R.A., has kindly furnished the following interesting observations on the 
subject:—“ In any comparison of guns where the conditions are so different, it is very difficult to 
assign values to different parts of the same projectiles. Thus, the 96-pr. Gruson shot, of 336 lbs., 
consisted of a lead jacket of 63 lbs. and an iron shot of 273 lbs. It is an open question which 
weight we should assume in making a comparison of vis viva. There cannot be a doubt that 
the 63 lbs. of lead is less effective than if it were 63 lbs. of iron; but has it no effect whatever ? 
On the whole, the fairest way is to take the absolute weight of projectile which strikes the target. 
If the Prussian system necessitates the use of 63 lbs. of useless material on a 3361b. shot, it is a 
decided disadvantage to the system. In the same manner, we have no data to guide us as to the 
diameter of the iron part of the Prussian shot. We know the calibre of the gun, and we know 
also that the shot with its lead jacket must be of the same diameter as the calibre of the gun, 
