88 INDIANA HISTORICAL COLLECTIONS 



As your letters written during your travels over the 

 country are read with so much pleasure by all your nu- 

 merous acquaintances, as well as those of your corre- 

 spondent D.C, I hope one or both of you will find it con- 

 venient to visit this part of Mississippi, and publish your 

 opinion as to how and when that great deposit was made. 



I wish to know whether there is good ground for be- 

 lieving that the Cumberland mountains once extended 

 across the Mississippi and united with those now seen in 

 the southwest part of Missouri, by which all the country 

 between the Alleghanies and Rocky mountains was cov- 

 ered with an immense Lake, and when the gap where the 

 great river now flows, was thrown down by the earth- 

 quakes that still continue their operations, in the same 

 vicinity, if the enormous mass of alluvial deposit below 

 was then made, which has since been disturbed and 

 thrown into all sorts of odd shaped hills by the further 

 action of volcanic power. I am sure the world would be 

 interested in reading your opinion upon this matter, 

 after examining the country indicated. I am sure you 

 would be interested in the examination. 



My present residence is near the head of Lake Michi- 

 gan, where the action of water in the formation of all the 

 land around me is very visible. The surface is black, 

 vegetable mold, with a trace of beach sand, lying upon a 

 bed varying from one to fifty feet of very hard yellowish 

 brown clay, that breaks out in cubes, and is intermixed 

 with flat gravel in small quantities, and sometimes boul- 

 ders, which are very frequent on the surface. Under 

 the clay lies clean beach sand, just as it was deposited by 

 the waves. A few feet into this sand clear water is 

 always found. In some places the sand comes to the sur- 

 face without any intervening clay. There are no rocks 

 either primitive or secondary in this part of Indiana. 

 But within a few miles of the State line over in Illinois, 

 the limestone crosses out, and 40 miles west, at Joliet, the 

 bottom of the O'Plain river is solid limestone. The origi- 

 nal bed of this river is a mile wide, channel cut down into 



