In war, the success of the most judicious plans often depends on accidents not to be foreseen nor controlled. Seldom has the truth of this proposition been more clearly demonstrated, than in the issue of the expedition conducted by Colonel Arnold. The situation of Canada conformed exactly to the expectations of the American general. Not suspecting that so bold and difficult an enterprise could be meditated, its Governor had left Quebec entirely defenceless, and had drawn the strength of the province towards the lakes. Could Arnold have reached that place a few days sooner--could he even have crossed the river on his first arrival at Point Levi--or had Colonel Enos been able to follow the main body with his division of the detachment--every probability favours the opinion, that this hardy and well conceived expedition would have been crowned with the most brilliant success. Nay, more--had Arnold been careful to relieve the inhabitants of the town from all fears respecting their property, there is reason to believe, they would have refused to defend it. But although this bold enterprise was planned with judgment, and executed with vigour; although the means employed were adequate to the object; yet the concurrence of several minute and unfavourable incidents entirely defeated it, and deprived it of that eclat to which it was justly entitled. {December 5.} Having clothed his almost naked troops at Montreal, General Montgomery, at the head of about three hundred men, proceeded with his usual expedition to join Colonel Arnold at Point Aux Trembles, where he supplied the troops of that officer with clothes provided at Montreal; and afterwards marched with their united forces directly to Quebec. But, before his arrival, Governor Carleton, who had entered the town, was making every preparation for a vigorous defence. The garrison now consisted of about fifteen hundred men, of whom eight hundred were militia, and between four and five hundred were seamen. Montgomery's effective force was stated, by himself, at only eight hundred. His situation would have filled with despair a mind less vigorous, less sanguine, and less brave. His numbers were not sufficient to render success probable, according to any common principle of calculation; and the prospect of their being diminished might be rationally entertained. But, relying on their courage, on himself and his fortune, and on the fears of the garrison; stimulated, too, by the high expectations formed throughout America of his success, and by the dread of disappointing those expectations, he determined to lay immediate siege to the town. [Sidenote: Montgomery lays siege to Quebec.] In a few days he opened a six gun battery within seven hundred yards of the walls; but his artillery was too light to make a breach, and he did not calculate on any effect from it. His object was to amuse the garrison, and conceal his real design.