DILUVIUM. 



279 



CHAPTER XXVI. 



GEOLOGY OF THE UNITED STATES— (Continued). 



ALLUVIAL AND DILUVIAL FORMATIONS. 



Diluvium. — Causes of Diluvial Deposites. — General Deluge.— 

 Existing Causes. — Diluvium of Cape Cod. — Alluvium. — 

 Where Found. — Banks of Rivers.— Seas. — Lakes. — Long Isl- 

 and.— Dunes or Downs. — How Found. — Phenomena of. 



Diluvium.— We have defined diluvium to consist of 

 gravel, bowlders,* sand, and loam, and mixed con- 

 fusedly together by powerful currents of water. Of 

 course it occupies much of the surface throughout 

 a great portion of the United States, and it is im- 

 possible, in a work like the present, to attempt to 

 give a complete description of its localities. It has 

 generally been attributed to the agency of a general 

 deluge, and most geologists have formerly been 

 willing to acknowledge that the phenomena con- 

 nected with it might all have been occasioned by 

 that described in the Bible. There are others, how- 

 ever, such as Mr. Lyell, who attempt to show that 

 these phenomena might all have been produced by- 

 causes now in operation, and such as we have 

 pointed out in our chapters on the destruction and 

 formation of rocks, viz., rivers, rain, frosts, &c. 

 This theory, however, is so little satisfactory, that 

 we do not deem it necessary even to attempt to 

 refute it. The hypothesis, however, that the phe- 

 nomena in question are the result of different floods, 

 produced by the elevation of rock strata at various 



* Rocks and stones which have been transported from their 

 original beds, and a#e, generally, more or less rounded by attri- 

 tion and the ac tion of the water. 



