162 
SHORT NOTES ON PROFESSIONAL SUBJECTS. 
101. Account of the Bursting of an 11-in. Cast Steel Krupp Gun, 
at Cronstadt, on Sept. 29, 1871. Extracted from the “Archiv fur die 
Artillerie und Ingenieur Offiziere des deutschen Reichsheeres.” Berlin, 1872. 
(Communicated by Lieut. E. E. B. Loraine, R.H.A.) 
An article which lately appeared in the Russian “ Invalides,” and was from 
thence transferred to the “ Militair Wochenblatt,” relative to the bursting of an 
11-in. Krupp gun at Cronstadt, on October 11, 1871, is worthy of notice. As, 
however, the explanation of the mishap which is there attempted contains so much 
that is unintelligible, and, as far as it is intelligible, admits of serious question, we 
purpose, before placing it before our readers, to offer the following sketch of the 
attendant circumstances. 
The front conical part of the gun burst as far as the front strengthening ring on 
the first occasion of being fired with a charge of 90 lbs. of prismatic powder and a 
double shell weighing 495 lbs., after two rounds had already been fired with 64 lbs. 
of prismatic powder. The cone broke into two parts, the line of breakage being 
nearly perpendicular to the axis of the piece; the rear and shorter part (about a third 
of the length of the cone) was itself separated into two smaller pieces by a longi¬ 
tudinal fracture. The front part was burst into four larger pieces. The broken 
surface of the body of the gun ran irregularly, partly under the ring, partly outside 
it, and the bursting took place (probably) when the base of the shell was from two 
to three feet from the muzzle of the gun. The gases which streamed out of the 
broken part of the gun to the rear knocked down part of the gun detachment, with¬ 
out, however, injuring anyone. Some of the fragments which flew to the rear con¬ 
formed precisely to the direction imparted to the gun on recoil; others fell straight 
to the ground. Of those which flew to the front, two fragments ricochetted several 
times on the ground, and eventually settled in the sea, at a distance of about 
38 yds. from the gun, conforming in their flight to the direction of the projectile. 
One of the latter fragments has already been recovered. A larger fragment, which 
was broken off close to the strengthening ring, still lies in the sea. 
To judge from the appearance of the broken surface, the steel was faultless, so no 
blame can be attributable to it; and by means of several impressions of the lands 
and grooves taken at the place where, from the surface of the fracture, we may 
infer that the breakage began, the probable conclusion has been arrived at that the 
shell was jammed in the bore. Precisely the same arrangements were made for 
loading with the double shell as with shot of ordinary length, so that the powder 
chamber was shortened by about 2*3 in., and the pressure on the shell and the bore 
consequently increased. In addition to this, some of the other double shells which 
were experimented with displayed a very porous surface. 
At the manufactory the following rounds were fired out of the gun—viz., one 
with 66, one with 77, and four with 88 lbs. of prismatic powder, and in each case a 
full sized projectile weighing 517 lbs. 
We now proceed to quote the article extracted by the “ Militair Wochenblatt,” 
from the Russian “ Invalides 55 
“ The chase or unstrengthened part of the gun burst on the first occasion that it 
was subjected to a charge of 100 lbs. (Russ.) of prismatic powder, and a projectile 
