“Within the last few days,” he wrote to Prevost, September 21,[136] “the sickness of the troops has increased to such an alarming degree, and their situation has really become one of such extreme wretchedness from the torrents of rain which have continued to fall for the last thirteen days, and from the circumstance of the Division being entirely destitute of camp-equipage, that I feel it my duty no longer to persevere in a vain attempt to maintain the blockade of so vastly superior and increasing a force of the enemy under such circumstances. I have therefore given orders for the troops to fall back toward the Chippawa, and shall commence my movement at eight o’clock this evening.” CHAPTER IV. WEAK as was the army at Niagara, it was relatively stronger than the defence at any other threatened point. Sackett’s Harbor contained only seven hundred effectives.[137] On Lake Champlain, Major-General Izard tried to cover Plattsburg and Burlington with about five thousand regular troops.[138] Already Armstrong knew that large British reinforcements from Wellington’s army were on their way to Canada;[139] and within a few weeks after the battle of Lundy’s Lane eleven thousand of the best troops England ever put in the field were camped on or near the Sorel River, about to march against Izard’s five thousand raw recruits. They could march nowhere else. Not only was the line of Lake Champlain the natural and necessary path of an invading army, but the impossibility of supplying any large number of troops in Upper Canada made Lake Champlain the only region in which a large British force could exist. Sir George Prevost had reached the limit of his powers in defending Upper Canada. His commissary-general, W. H. Robinson, wrote to him, August 27, expressing “the greatest alarm” on account of deficient supplies at Burlington Heights and Niagara, where instead of nine thousand rations daily as he expected, he was required to furnish fourteen thousand, half of them to Indians.[140] Much as Prevost wanted to attack Sackett’s Harbor, and weak as he knew that post to be, he could not attempt it, although he had thirteen or fourteen thousand rank-and-file idle at Montreal. In October he went to Kingston expressly to arrange such an attack, and found it impossible.