as illustrating the Geology of North America. 21 



this wide region*, and its absorbent and cavernous nature 

 prevents swamps and moisture from accumulating on its sur- 

 face. The mineral resources of these plains are unbounded, 

 and its coal-field would cover half Europe. The coal is pure, 

 lies above the level of the river channels, and is easily worked. 

 Iron and lead are also abundant. Salt water is found over 

 the whole extent, and yields from £th to y^th of its weight in 

 pure muriate of soda. This salt water breaks out in many 

 places in the form of springs ; but it is more usually necessary 

 to bore to the depth of from 3 to 600 feet into the limestone. 

 Gypsum and saltpetre are found in abundance, and most of 

 the earths or clays useful in the arts." 



There is probably no part of the world of a similar extent 

 that more completely points out its own history and forma- 

 tion than these North American plains. We here find re- 

 posing on a marine formation, the depth of which is unknown, 

 and which remains in an undisturbed level surface, all the 

 marks we can desire or expect of diluvial deposits in the form 

 of deep beds of clay and gravel containing the fossil remains 

 of the Elephant, the Mastodon, and other contemporaneous 

 animals ; and also extensive strata of pure vegetable and bitu- 

 minous coal, as well as the chemical formations of ironstone, 

 gypsum, lead, &c. From the great extent and level nature 

 of the original sea bed here laid dry, the diluvial deposits 

 have also assumed the same regularity of form ; so that the 

 researches of the geologist are infinitely less complex than in 

 our own island, where we have, crowded into a small district, 

 a confused mixture of every description, which has given rise 

 to much difficulty, and to a wide field of theoretical specula- 

 tion, contributing largely to give to this interesting study that 

 doubtful and obscure character of which it is, in fact, unde- 

 serving, when viewed upon a wide and proper basis. Had 

 this science taken its rise in America instead of in Italy and 

 in England, the more enlarged scale of things, and the more 

 simple nature of the formations, would have led to that corre- 

 sponding simplicity which true geology possesses. But in the 

 microscopic views of things which are alone within the reach 

 of our personal inspection, in the most scientific parts of Eu- 

 rope, we can scarcely wonder at the extraordinary ideas which 

 have arisen on this subject, and which have naturally spread 

 with civilization into other more extensive regions, to which 

 they cannot possibly be consistently applied. Instead, then, of 

 making our confined districts the arena of geological illustra- 



* This is a point which is more than questionable. The fertility of this 

 wide region is in great part owing to the alluvial or diluvial soils which 

 cover its whole extent to a greater or less depth, and in which the fossil 

 remains of Mammalia unnatural to America are so constantly found. 



