After leaving Medium Lake evidences of the presence of Indians were observed from time to time. What appeared to be moccasin tracks were frequently seen. Cattle had been killed in such a manner as to leave no doubt that the work had been done by Indians. At Big Island Grove many signs of Indians were found. On an island in the middle of the lake the Indians had constructed a look-out in the tree-tops from which they were able to see the country for miles around. Better evidence still of the fact that their visits were recent was the report that the campfires were still glowing, and that fishing holes were found in the ice.[250] Many members of the expedition believed that the Indians, after raiding the settlements at the lake, would cross over to the Des Moines and proceed south on a war of extermination; and the signs at Big Island Grove were very readily accepted as a substantiation of this belief. It is probable, however, that this was a mistaken conclusion. Sleepy-Eye had frequently rendezvoused at Big Island Grove, and the arrival of the expedition may have followed closely his departure on the spring hunting trip. It is not probable that Inkpaduta’s men went east of the lakes or south of Springfield. On the evening of the arrival of the expedition at Big Island Grove, Major Williams decided that since they were evidently in the Indian country the march should thereafter be made with more caution. Accordingly, he called for volunteers for an advance scouting party of ten men whose work would be to precede the main expeditionary force and keep a sharp look-out for the near approach of Indians and to observe, interpret, and report any signs that might be discovered. They were to maintain an advance of perhaps three miles over the main column. Major Williams selected as the commander of this advance guard William L. Church, who of all the members of the expedition was the most familiar with the country in which they were now moving, since he had passed through it a number of times after settling at Springfield. Those who had volunteered as his companions were Lieutenant Maxwell, Thatcher, Hathaway, F. R. Mason, Laughlin, A. S. Johnson, De Foe, Carpenter, and another man whose identity seems to have been forgotten shortly after the return of the expedition to Fort Dodge.[251]