At Sault Ste. Marie Mr. Schoolcraft became acquainted with Mr. John Johnston, a gentleman from the north of Ireland, who had long resided there, and in the person of his eldest daughter married a descendant of the hereditary chief of Lake Superior, or Lake Algoma, as it is known to the Indians. She had been educated in Europe, and was an accomplished and highly interesting woman. After a residence there of eleven years he removed to Michilimackinac, and assumed the joint agency of the two districts. In 1836 he was appointed by President Jackson a commissioner to treat with the north-west tribes for their lands in the region of the upper lakes, and succeeded in effecting a cession to the United States of some sixteen millions of acres. In the same year he was appointed acting Superintendent of Indian Affairs for the Northern Department, and in 1839 principal disbursing agent for the same district. In the last mentioned year he published two volumes of Algic Researches, comprising Indian Tales and Legends, and soon after, having passed more than twenty years as a traveller or resident on the frontiers, he removed to the city of New-York, intending to prepare for the press the great mass of his original papers which he had accumulated in this long period. In 1841 he issued proposals for an Indian Cyclopedia, geographical, historical, philological, etc., of which only one number was printed, no publisher appearing willing to undertake so costly and extensive a work of such a description. In 1842 he visited England, France, Germany, Prussia, and Holland. During his absence his wife died, at Dundee, in Canada West, where she was visiting her sister. Soon after his return he made another journey to the west, to examine some of the great mounds, respecting which he has since communicated a paper to the Royal Geographical Society of Denmark, of which he was many years ago elected an honorary member, and soon after published a collection of his poetical writings, under the title of Alhalla, or the Lord of Talladega, a Tale of the Creek War, with some miscellanies, chiefly of early date. In 1844 he commenced in numbers the publication of Oneota, or the Red Race in America, their History, Traditions, Customs, Poetry, Picture Writing, etc., in extracts from Notes, Journals, and other unpublished writings, of which one octavo volume has been completed. In 1845 he delivered an address before a society known as the "Was-ah Ho-de-no-sonne, or New Confederacy of the Iroquois," and published Observations on the Grave Creek Mound in Western Virginia, in the Transactions of the American Ethnological Society; and early in the following year presented in the form of a Report to the legislature of his native state, his Notes on the Iroquois, or Contributions to the Statistics, Aboriginal History, and General Ethnology of Western New-York.