When the Cabinet realised that Boston was in great want of food they sent out many ships filled with stores of every kind. But the ill-luck which dogged the British throughout the American war prevented the arrival of these vessels. Some were lost at sea; others were blown by a tempest to the West Indies; while others again, laden with cannon and mortars, muskets, flints, and much powder and shot fell into the hands of the Americans, who under Washington’s fostering care were rapidly forming a national fleet. These munitions of war were not the only provincial spoils: a daring raid against isolated forts on the Canadian frontier secured a large number of guns, and early in March, 1776, Washington began to bombard Boston with British ordnance, and took possession of high ground to the south of the town, which from want of men neither Gage nor his successor Howe had been able to include within their lines. This position commanded the harbour, and the Admiral warned the General plainly that unless the soldiers could recapture it the men-of-war and transports would be obliged to put to sea. Thereupon Howe, who had long realised that it was impossible to maintain himself in Boston, ordered its evacuation, and on the 17th of March, with the nine thousand troops remaining to him and eleven hundred loyalists who refused to remain behind, he set sail for Halifax in Nova Scotia, in ships so overcrowded that many valuable stores had to be left to fall into Washington’s hands, while much of the officers’ heavy baggage shared the same fate. The Americans did not hinder the embarkation, for Howe had given out that if the bombardment was resumed he would set fire to the town, and Washington, to whom the threat was reported by his spies, allowed him to depart in peace. The men-of-war, after seeing the troopships safely out to sea, hung about the coast of Massachusetts for a time, but effected nothing, and then were ordered to other parts of the theatre of war.