Richelieu River, which flows north from Lake Champlain. He decided that the defences on this obvious route were too strong and instead shifted westward to Four Corners, on the Chateauguay River near the border with Canada. He was forced to wait there for several weeks as Wilkinson's force was not ready, which cost him some of his initial advantage in numbers as Canadian troops were moved to the Chateauguay, and reduced his supplies. Armstrong had intended that Wilkinson's force would set out on 15 September. On 2 September, Wilkinson himself had gone to Fort George, which the Americans had captured in May, to arrange the movement of Brigadier General John Parker Boyd's division from Fort George to rendezvous with the troops from Sackett's Harbor. Possibly because he was ill, he delayed around Fort George for nearly a month. He returned to Sackett's Harbor, and Boyd's division began its movement, only in the first week in October. The poor prospects for success (and possibly his own illness) led Armstrong to abandon his intention of leading the final assault himself. He handed overall command of the expedition to Wilkinson and departed Sackett's Harbor on his way to Washington on 16 October, just before Wilkinson's part of the campaign was at last launched. Armstrong's letter to Hampton, notifying him of the change in command and also throwing much of the burden of supplying the combined force onto him, arrived the evening before Hampton's army fought the Battle of the Chateauguay. Although Hampton nevertheless attacked, as part of his force was already committed to an outflanking move, he immediately sent his resignation, and fell back when his first attack was repulsed. Wilkinson's moves Wilkinson's force left Sackett's Harbor in 300 batteaux and other small craft on 17 October, bound at first for Grenadier Island at the head of the St. Lawrence. Mid-October was very late in the year for serious campaigning in the Canadas and the American force was hampered by bad weather, losing several boats and suffering from sickness and exposure. It took several days for the last stragglers to reach Grenadier Island. On 1 November, the first boats set out from the island, and reached French Creek (near present-day Clayton, New York) on 4 November. Here, the first shots of the campaign were fired. British brigs and gunboats under Commander William Mulcaster had left Kingston to rendezvous with and escort batteaux and