But already a sufficient number of Indians had come to the aid of the English to render service. On the very next day the English flag replaced the American above the fort at Mackinac. No sooner had the news of the beginning of hostilities become known at the neighboring British post at St. Joseph's than immediate preparations were made. The Indians were marshalled for the attack, and a vessel belonging to the North West Company was requisitioned. The morning of July 17th revealed the American fort surrounded by Indians and commanded by a cannon which had been dragged upon a height of land. Seeing the futility of resistance the garrison surrendered and marched out before noon. Of the total attacking force of 1021 there were Indians to the number of 715, of whom the British leader wrote, "although these people's minds were much heated, yet as soon as they heard the Capitulation was signed they all returned to their Canoes, and not one drop either of Man's or Animal's Blood was Spilt, till I gave an Order for a certain number of Bullocks to be purchased for them".[22] The ease with which the capture was made had the effect of bringing to the English standards all the Indians of the Northwest, except a part of the Miamis and Delawares, in spite of the fact that they had earlier made promises of neutrality.[23] Although the capture of the fort at Mackinac was accomplished without any Indian atrocities, the success of that day was to precipitate a massacre, long to rankle in the minds of the pioneers of the West. Immediately upon hearing of the capture of the fort, General Hull wrote to Captain Heald in command at Fort Dearborn ordering the evacuation of that post. On the morning of August 15th, as the small garrison of fifty-five regulars and twelve militia were leaving the fort with their women and children, they were fallen upon by a force of five hundred Indians. Twenty-six regulars, all the militiamen, two women, and twelve children were murdered on the spot. An unknown number of wounded prisoners were that evening victims at what the Indians termed a "general frolic".[24] In the meantime Robert Dickson, who for many years had been a Prairie du Chien fur trader, was continuing his activities as recruiter of Indians for British service. This was the same Dickson who had in 1802 received an American commission as a justice of the peace,[25] and had later entertained Pike and his men "with a supper and a dram", impressing the American explorer as a man of "open, frank manners."[26] Now, in January, 1813, he was appointed by Great Britain "agent for the Indians of the several Nations to the Westward of Lake Huron".[27]