MINUTES OF PROCEEDINGS OF 
142 
rection ” after each discharge had to be sent by means of a chain of posts along 
the trenches. The elevation finally determined was 7 J°, It varied to the 
extent of several sixteenths, on account of heavy rains and other meteoro¬ 
logical influences. The guns were laid with quadrants. The range was 
determined about noon, and the horizontal cut was at once commenced. 
When the horizontal cut was about half completed, a report was brought 
in that the system of countermines in front of the lunette had been pene¬ 
trated by a gallery driven from the 3rd parallel. From the opening of these 
galleries in the counterscarp the whole of the breach could be observed, and 
it was seen that the lowest point of impact of the shells was about one or two 
feet above the level of the water, as intended. The breaching fire was con¬ 
tinued for four days. 
The continued breaching did not form a perfectly horizontal cut; for in 
consequence of the shells straying upwards, the whole of the wall was 
demolished by degrees, and while the lower parts were being gradually cut 
through, the upper parts were destroyed, great masses falling down, succeeded 
by earth. It was therefore not necessary to make vertical cuts. A large 
number of shells were fired into the earth of the parapet, to bring it down. 
The breach had a slope of about 35°, and if a little more of the earth of 
the parapet had been brought down, the breach would have been prac¬ 
ticable. The breach was entered on the 20th September, when the lunette 
was found to be deserted. 
2. 'Bombardment of the two Sluices, (Vide sketch). 
One of the chief sources of strength of the fortress of Strasburg consists, 
as is pretty well known, in the obstacles presented by its wet ditches and 
by the extensive inundations which can be formed in its vicinity. 
By damming up the Ill and utilising the existing system of sluices, the 
Trench had not only filled the ditches of the fortress with water and inun¬ 
dated the whole country opposite the south front, but also a great part of 
the ground on the left flank of the attack, thereby considerably increasing 
the difficulties of the besieged approach. 
The existing plans of the fortress showed that the retention of the water 
in the ditches, and the swamping of the ground in front of the attack, was 
mainly effected by two sluices, one of which was situated in front of the 
curtain 15-16, and the other in front of lunette 63. By the destruction of 
these two outlet sluices it was hoped that the water on the attacking 
ground and in the ditches would be, if not actually drained, at any rate 
reduced to a very low level. 
Neither of the sluices could be seen from any part of the attacking 
ground. The inaccurate maps would not have afforded sufficient data to 
undertake the bombardment from the first parallel with any chance of 
success, had there not been an engineer officer (Captain Kirchgessner, of the 
Baden service) present at the siege, possessed of local knowledge, who could 
supply the necessary information. 
Under these circumstances, the officer commanding the siege artillery 
resolved at any rate to make the attempt. It was not deemed advisable to 
form a special battery for the purpose, but it was considered sufficient to 
