This fortress, although regularly constructed with six bastions, ravelins, an excellent ditch, and covered way, was extremely defective. The ramparts were too high for the glacis, and from some near ground, on the side of the attack, the bottom of the ditch might be seen. An old square castle, built on a mound in the centre of the town, contained three bomb proofs, the doors of which were not secure; but with the exception of some damp casements in one bastion, there was no other magazine for the powder. Colonel Cox was governor, and his garrison composed of one regular and two militia regiments, a body of artillery and a squadron of cavalry, amounted to about four thousand men. On the 18th, the trenches were begun under cover of a false attack, and in the morning of the 26th (the second parallel being commenced) sixty-five pieces of artillery mounted in ten batteries opened at once. Many houses were soon in flames and the garrison was unable to extinguish them; the counter fire was, however, briskly maintained, little military damage was sustained, and towards evening the cannonade slackened on both sides; but just after dark the ground suddenly trembled, the castle bursting into a thousand pieces, gave vent to a column of smoke and fire, and with a prodigious noise the whole town sunk into a shapeless ruin! Treason or accident had caused the magazines to explode, and the devastation was incredible. The ramparts were breached, the greatest part of the guns thrown into the ditch, five hundred people were struck dead on the instant, and only six houses left standing; the stones thrown out hurt forty of the besiegers in the trenches, and the surviving garrison, aghast at the horrid commotion, disregarded all exhortations to rally. Fearing that the enemy would take the opportunity to storm the ramparts, the governor beat to arms, and, running to the walls with the help of an artillery officer, fired off the few guns that remained; but the French shells fell thickly all the night, and in the morning of the 27th, two officers appeared at the gates, with a letter from Massena, offering terms.