140 
MINUTES OF PROCEEDINGS OF 
Every artilleryman knows the difficulty of making an efficient breach by 
curved fire with the present elongated projectile. In order that the shell 
may just lob over the glacis, and hit the escarp wall sufficiently low down to 
form a practicable breach, the projectile must have impressed on it a high 
“ angle of descentand this high angle of descent necessitates, at the ranges 
at which breaching batteries are opened, a high angle of elevation, and con¬ 
sequently a small charge. This small charge, as is well known, is productive 
of a “ wabbling” in the flight of the projectile, accompanied with slight 
penetrative power. It is consequently of importance to select the sites for 
breaching batteries at those distances (consistent with local requirements) 
from which the best effect from the gun can be produced. If tables w r ere 
prepared, giving the penetrative force corresponding to the angles of descent 
at different ranges and for different charges, the artilleryman could see at a 
glance the best distance of his battery to meet the object in view. 
At the siege of Strasburg, the Prussians used for breaching purposes the 
short 15 c.m. (6-in.) gun, firing a special long shell weighing about 60 lbs. 
They had carried out a series of breaching experiments with this gun at 
Silberberg, in 1869, and the experience gained from these trials, General 
von Decker tells us, proved exceedingly useful in the conduct of the siege. 
The method of breaching employed at Strasburg did not differ from that 
which is well known— i.e ., a horizontal cut was made at a height from the 
bottom equal to one-third of the wall, and when this cut w r as supposed to be 
satisfactorily effected, vertical cuts (if necessary) were made, first at the two 
ends of the horizontal cut, and subsequently at intermediate points, the con¬ 
tinued firing eventually bringing down the wall. Of course they could only 
conjecture when the horizontal cut was satisfactorily completed, but they 
could draw fairly correct inferences from certain phenomena exhibited at the 
practice ground at Silberberg, and which were found to be indicative of a 
successful breach. 
(1) The concussion and explosion of a shell has a hard sharp sound if it 
hits solid masonry; on the other hand, it has a hollow and faint sound if it 
hits masonry either wholly or partly broken through—in this latter case the 
shell exploding in the earth behind the wall. 
(2) Fragments of stone are hurled into the air as long as the masonry 
resists. 
(3) The smoke from the explosion of the projectile soon rises above the 
wall, is of a blueish tinge, and forms a “ball” if the masonry remains 
intact. If the masonry has been broken through, the smoke appears after 
some delay, is darkish grey in colour, and rises slowly, as if coming from a 
chimney-pot. 
General von Decker states that account was taken of these phenomena 
at Strasburg, and that when satisfactory appearances were observed, the 
“ vertical cuts ” w r ere proceeded with, and generally effected in a short space 
of time. 
There were two breaches in Strasburg which were nearly or quite practi¬ 
cable :—(1) Breach on right face of lunette No. 53. Took four days (14-17 
September). About 1000 rounds were fired, each gun firing at the rate of 
50-70 rounds per day of 12 hours (7 a.m. to 7 p.m.) Unfavourable 
weather, and a want of training on the part of the gunners, delayed the com- 
