The original circular recites that it was addressed to four classes of individuals, namely, “I. Persons holding positions under the department, who are believed to have it in their power to impart much practical information respecting the tribes who are, respectively, under their charge. II. Persons who have retired from similar situations, travelers in the Indian Territory, or partners and factors on the American frontiers. III. Men of learning or research who have perused the best writers on the subject and who may feel willing to communicate the results of their reading or reflections. IV. Teachers and missionaries to the aborigines.” The circular closes with an expression of the “anxiety which is felt to give to the materials collected the character of entire authenticity, and to be apprised of any erroneous views in the actual manners and customs, character, and condition of our Indian tribes which may have been promulgated. The Government, it is believed, owes it to itself to originate a body of facts on this subject of an entirely authentic character, from which the race at large may be correctly judged by all classes of citizens, and its policy respecting the tribes under its guardianship, and its treatment of them, properly understood and appreciated.” The 348 inquiries in the circular embrace the history (and archeology), the tribal organization, the religion, the manners and customs, the intellectual capacity and character, the present condition, the future prospects, and the language, of the Indian tribes of the United States. But the report of Mr. Denig consists of brief and greatly condensed replies to as many of the questions propounded in the circular in question as concerned the native tribes of the upper Missouri River, to wit, the Arikara, the Mandan, the Sioux, the Gros Ventres, the Cree, the Crows, the Assiniboin, and the Blackfeet, tribes with whom he was thoroughly acquainted, although the Assiniboin seem to have been the chief subjects of his observations. It should be noted that the answers to some of the questions, if adequately treated, would have required nearly as much space as was devoted to the entire report. While the facts embodied in the replies of Mr. Denig are, when unqualified, affirmed of all the eight tribes mentioned in his letter of transmittal, he is nevertheless careful, when needful, to restrict many of his answers to the specific tribes to which their subject matter particularly related. But, of course, all the tribes mentioned belonged measurably to a single cultural area at that time. That Mr. Denig made use of the circular issued by Mr. Schoolcraft is clearly evident from the fact that on the left-hand margin of the manuscript he usually wrote the number of the question to which he was giving an answer. In the manuscript there appear two quite distinct handwritings, and so it is possible that this particular manuscript is a copy of an original which was retained by the author.