The French, whose operations were hidden by the gardens, at once proceeded to drive a gallery in order to blow up the counterscarp, upon which their guns could not be brought to bear, and on the 29th the mine was sprung. It did some damage, but it had not been driven quite far enough. Led by an officer of the staff named Mailly, the French rushed forward as soon as the mine exploded. They clambered down over the breach that had been made on the counterscarp, crossed the fosse by three ladders they had brought with them, and reached the foot of the breach. There was, however, too great a distance between the pile of rubbish at the foot of the wall and the great hole above it for them to enter without fixing their ladders.