In the summer of 1830 Mr. Ayer went to La Pointe, Lake Superior, with Mr. Warren, opened a school and commenced the study of the Ojibway language. In 1831 he met at Mackinaw, Revs. Hall and Boutwell, who were sent out by the American Board of Commissioners for Foreign Missions to the Indians, and he returned with Mr. and Mrs. Hall and their interpreter to spend another winter at La Pointe. The next year, 1832, Mr. Ayer wintered with another trader at Sandy Lake. He opened a school there and completed a little Ojibway spelling book which was commenced at La Pointe. In the spring of 1833 he left Sandy Lake for Utica, New York, to get the book printed. Mr. Aitkin, with whom he had wintered, gave him eighty dollars, and with a pack on his back and an experienced guide, he started on his journey. Before they reached Sault Ste. Marie the ice on Lake Superior was so weak that Mr. Ayer broke through and was saved only by carrying horizontally in his hands a long pole to prevent his sinking. Mr. Ayer hastened on to complete the object of his journey, that he might return to Mackinaw in time to go up Lake Superior with the traders. Mr. Ayer, hitherto an independent worker, now put himself under the direction of the "American Board," and was sent to Yellow Lake, within the present bounds of Burnett county, Wisconsin. Miss Delia Cooke, whose name should never be forgotten among the early missionaries of the American board to the Indians, and Miss Hester Crooks, a girl educated at Mackinaw, and who had some experience in teaching, were among the number who coasted up Lake Superior in a Mackinaw boat; the former to La Pointe mission, the latter to Yellow Lake with Mr. and Mrs. Ayer. They wintered in Dr. Borup's family. Mrs. Borup also had, for some years, been a pupil at Mackinaw. The next year Miss Crooks married Rev. Mr. Boutwell and went to Leech lake, and J. L. Seymour and Miss Sabrian Stevens, also Henry Blatchford, an interpreter from Mackinaw, were added to Yellow Lake mission. When Mr. Ayer told the Indians his object in coming among them, they gave him a welcome. But six months later, seeing two or three log houses in process of building, they were much troubled, and met in a body to request him to go away. A Menomonie from the region of Green Bay had stirred them up, not against the missionaries, but against the general government.