430 CASTS OF MUD FURROWS, WAVE LINES, &C. 



indeed, as to allow of specific distinctions being founded on these 

 characters alone. 



After such proofs as these, we cannot doubt the first; indeed, 

 the one corroborates the other ; and although in the wave lines we 

 may never find other proof than that afforded by analogy, or com- 

 parison with recent effects of the same kind, yet the resemblance 

 is so impressive, that we cannot doubt. In the case of the foot- 

 prints, we have both analogy, and in some cases, already, demon- 

 strative proof. In the wave lines, the analogy is equally strong 

 as in the foot-prints, before bones had been found, which indicate 

 an animal capable of making such impressions. 



Believing that we shall be willing to admit this as a new fact 

 in physical geology, the age of the rocks in which these marks 

 occur, enables us to extend back, for a long period, our ideas 

 of the time when nature operated as she now does, by winds and 

 waves, upon the present shores ; and it follows, too, that the limits 

 of the ancient ocean did not every where extend to the great pri- 

 mary chain of mountains at the East. 



During the last summer I have had the pleasure of reexamin- 

 ing these markings upon the rocks, as well as witnessing again 

 the effects of waves upon the sandy shores of our lakes, in com- 

 pany with our distinguished visiter, Mr. Lyell, and I am happy 

 to say, that his opinion confirms what I have here stated, and en- 

 courages me to offer the facts to the notice of geologists, hoping 

 that they may be found of interest and importance. 



From the course of these wave lines we learn, thai the wind 

 was generally in the direction from the north-northwest, or va- 

 rying from northwest to north, proving that the sm-face was higher 

 to the southeast, for a wave line cannot be made upon a perfectly 

 horizontal sm-face, although a ripple-mark may. The dip of the 

 strata is now southward, the surface inchning in an opposite direc- 

 tion from what it did at the period of deposition. In the numerous 

 specimens and surfaces which I have examined at the quarries, 

 the direction of the wind appears to have been uniform during 

 successive depositions. " This constant direction of the wind from 

 one quarter would indicate that there were no extensive highlands 

 in the vicinity, as these would have more or less influenced the 

 direction. 



