On the fifteenth night these works would be completed; then, if they had been obliged to dig a fourth parallel, they would diverge from that in two saps which would unite to form a strong traverse, under shelter of which these saps would reach as far as the salient of the re-entering _place d'armes_, which they would crown by extending that crowning right and left. They would then have to commence the descent of the ditch. During the sixteenth night the breach batteries would be terminated, and would begin firing. They would work at the descent of the ditch. If possible, they would get down into the _place d'armes_ to install themselves and plant a battery of stone mortars there. The seventeenth night would be occupied in finishing the descent to the ditch, and they would commence the epaulement of the passage. During the eighteenth night they would begin to make a breach, and advance the passage of the ditch of the breach, which should be effected in the morning. During the nineteenth night they would reconnoitre the breach, and the sappers would render it practicable. They would terminate the epaulements of the passage of the ditch, that the assault might be made next day. Thus, according to the plan of the siege, in nineteen times twenty-four hours the place would be in the power of the enemy. The lines were fixed upon, and General Werther did not doubt of success, as he did not imagine that La Roche-Pont could be succoured, and was aware of the weakness of the garrison and the inefficient character of its artillery. Nevertheless, these theoretic calculations were somewhat disconcerted by the energy of the defence. Colonel Dubois had not men enough to act efficiently at a distance; he did his utmost to economise his strength, and contented himself with impeding the works at the commencement with his artillery. This consisted, as we have seen, of-- Guns of various calibre 20 Twenty-four pounders 6 Howitzers 2 Mortars 4 Field-pieces 4 -- Total of ordnance 36 == A dozen stone mortars and rampart rifles formed the rest of the artillery. The arsenal contained also a certain supply of hand-grenades and fireworks.