32 PRELIMINAEY DOCUMENTS. 



with the means in my power, will be given by the Department. 

 To this end, General Macomb will be ordered to afford you every 

 facility you may require. 



I have, &c., 



J. C. CALHOUN. 

 His Excellency, Lewis Cass, Detroit, M. T. 



III. 



Department of War, February 25, 1820. 



Sir : Mr. Schoolcraft, a gentleman of science and observation, 

 and particularly skilled in mineralogy, has applied to me to be 

 permitted to accompany you on your exploring tour upon Lake 

 Superior. I have directed him to report to you, for that duty, 

 under the belief that he will be highly useful to you, as well as 

 serviceable to the Government and the promotion of science. 



You will furnish him with the necessary supplies and accommo- 

 dation while employed, and every facility necessary to enable him 

 to obtain a knowledge of the mineralogy of the country as far as 

 practicable. 



I have, &c., 



J. C. CALHOUN. 

 His Excellency, Lewis Cass, Detroit. 



IV. 



Detroit, March 10, 1820. 



Sir : I have the honor to acknowledge the receipt of your let- 

 ter of the 17th ult., inclosing a copy of a letter from Giles San- 

 ford & Co. 



Their statement with respect to the discovery of plaster of 

 Paris upon one or more of the islands in the vicinity of Michili- 

 mackinac, to which the Indian title has not been extinguished, is 

 correct. Specimens of this plaster have been brought here, and 

 it is reported, by competent judges, to be of the best and purest 

 kind. The quantity is stated to be inexhaustible, and, as vessels 

 generally return empty, or nearly so, from the upper lakes, it 

 could be transported to any part of Lake Erie at a trifling expense. 



I have great doubts, however, whether it would be proper for 

 the Government to grant any permission to remove this plaster 

 until the Indian title to the land is extinguished. The power of 



