Despairing of reducing the fortress by other means, the French now brought up cannon, and it was not till the 14th of May that all was ready, and that the last and grand assault was made. Across the ravine in which the conflict we have just described took place, an immense knoll juts out, at an equal level with the lower entrenchments of the Waldenses. To this rock the cannons were hoisted up to play upon the fortress.[143] Never before had the sound of artillery shaken the rocks of San Martino. It was the morning of Whit-Sunday, and the Waldenses were preparing to celebrate the Lord’s Supper, when the first boom from the enemy’s battery broke upon their ear.[144] All day the cannonading continued, and its dreadful noises, re-echoed from rock to rock, and rolled upwards to the summits of the Col du Pis and the Mont Guinevert, were still further heightened by the thousands of musketeers who were stationed all round the Balsiglia. When night closed in the ramparts of the Waldenses were in ruins, and it was seen that it would not be possible longer to maintain the defence. What was to be done? The cannonading had ceased for the moment, but assuredly the dawn would see the attack renewed. Never before had destruction appeared to impend so inevitably over the Vaudois. To remain where they were was certain death, yet whither could they flee? Behind them rose the unscalable precipices of the Col du Pis, and beneath them lay the valley swarming with foes. If they should wait till the morning broke it would be impossible to pass the enemy without being seen; and even now, although it was night, the numerous camp-fires that blazed beneath them made it almost as bright as day. But the hour of their extremity was the time of God’s opportunity. Often before it had been seen to be so, but perhaps never so strikingly as now. While they looked this way and that way, but could discover no escape from the net that enclosed them, the mist began to gather on the summits of the mountains around them. They knew the old mantle that was wont to be cast around their fathers in the hour of peril. It crept lower and yet lower on the great mountains. Now it touched the supreme peak of the Balsiglia. Will it mock their hopes? Will it only touch, but not cover, their mountain camp? Again it is in motion; downward roll its white fleecy billows, and now it hangs in sheltering folds around the war-battered fortress and its handful of heroic defenders. They dared not as yet attempt escape, for still the watch-fires burned brightly in the valley. But it was only for a few minutes longer. The mist kept its downward course, and now all was dark. A Tartarean gloom filled the gorge of San Martino.