Montcalm's position certainly looked secure for the summer. His left flank was guarded by the Montmorency, a swift river that could be forded only by a few men at a time in a narrow place, some miles up, where the dense bush would give every chance to his Indians and Canadians. His centre was guarded by entrenchments running from the Montmorency to the St Charles, six miles of ground, rising higher and higher towards Montmorency, all of it defended by the best troops and the bulk of the army, and none of it having an inch of cover for an enemy in front. The mouth of the St Charles was blocked by booms and batteries. Quebec is a natural fortress; and above Quebec the high, steep cliffs stretched for miles and miles. These cliffs could be climbed by a few men in several places; but nowhere by a whole army, if any defenders were there in force; and the British fleet could not land an army without being seen soon enough to draw plenty of defenders to the same spot. Forty miles above Quebec the St Lawrence channel narrows to only a quarter of a mile, and the down current becomes very swift indeed. Above this channel was the small French fleet, which could stop a much larger one trying to get up, or could even block most of the fairway by sinking some of its own ships. Besides all these defences of man and nature the French had floating batteries along the north shore. They also held the Levis Heights on the south shore, opposite Quebec, so that ships crowded with helpless infantry could not, without terrible risk, run through the intervening narrows, barely a thousand yards wide. A gale blowing down-stream was the first trouble for the British fleet. Many of the transports broke loose and a good deal of damage was done to small vessels and boats. Next night a greater danger threatened, when the ebb-tide, running five miles an hour, brought down seven French fireships, which suddenly burst into flame as they rounded the Point of Levy. There was a display of devil's fireworks such as few men have ever seen or could imagine. Sizzling, crackling, and roaring, the blinding flames leaped into the jet-black sky, lighting up the camps of both armies, where thousands of soldiers watched these engines of death sweep down on the fleet. Each of the seven ships was full of mines, blowing up and hurling shot and shell in all directions. The crowded mass of British vessels seemed doomed to destruction. But the first spurt of fire had hardly been noticed before the men in the guard boats began to row to the rescue. Swinging the grappling-hooks round at arm's length, as if they were heaving the lead, the bluejackets made the fireships fast, the officers shouted, 'Give way!' and presently the whole infernal flotilla was safely stranded. But it was a close thing and very hot work, as one of the happy-go-lucky Jack tars said with more force than grace, when he called out to the boat beside him: 'Hullo, mate! Did you ever take hell in tow before?'