He was too far removed from the inhabited country to hope for support, and was too weak to maintain Kaskaskia and the Illinois against the combined force of regulars and Indians by which he was to be attacked so soon as the season for action should arrive. While employed in preparing for his defence, he received unquestionable information that Hamilton had detached his Indians on an expedition against the frontiers, reserving at the post he occupied only about eighty regulars, with three pieces of cannon and some swivels. Clarke instantly resolved to seize this favourable moment. After detaching a small galley up the Wabash with orders to take her station a few miles below Vincennes, and to permit nothing to pass her, he marched in the depth of winter with one hundred and thirty men, the whole force he could collect, across the country from Kaskaskia to Vincennes. This march, through the woods, and over high waters, required sixteen days, five of which were employed in crossing the drowned lands of the Wabash. The troops were under the necessity of wading five miles in water, frequently up to their breasts. After subduing these difficulties, this small party appeared before the town, which was completely surprised, and readily consented to change its master. Hamilton, after defending the fort a short time, surrendered himself and his garrison prisoners of war. With a few of his immediate agents and counsellors, who had been instrumental in the savage barbarities he had encouraged, he was, by order of the executive of Virginia, put in irons, and confined in a jail. This expedition was important in its consequences. It disconcerted a plan which threatened destruction to the whole country west of the Alleghany mountains; detached from the British interest many of those numerous tribes of Indians south of the waters immediately communicating with the great lakes; and had, most probably, considerable influence in fixing the western boundary of the United States. [Sidenote: Congress determine to attack Canada, and the other British possessions in North America.]