432 OAST.S OF MUD FURROWS, WAYK LINES, (Scc. 



It is not in lliis rock alone wlicro we have indications of re- 

 moval subsequent to deposition. In the western part of New 

 York, the strata associated with the Oriskany sandstone bear 

 equal evidence of having been acted upon by such forces, and the 

 result has been their partial or total destruction. In some in- 

 stances, the surfaces remaining are furrowed and channelled, as 

 by the wearing action of a powerful current, and they present 

 inequalities similar to the rocky bed of a stream or river. In no 

 case of this kind, however, have I been able to detect the grooved 

 and striated surface so common on our present rocks, the general 

 appeai'ance and the absence of masses being the sti'ongest ground 

 for this inference. 



In the existence of wave lines we have conclusive proof of the 

 existence of a sea-beach at this eai-ly period of the earth's history ; 

 a period when the ocean is supposed to have held universal do- 

 minion over the sm'face. And, although it may not indicate any 

 great extent of dry land, still it points to the operations which at 

 different subsequent periods have elevated these older deposits, 

 and to which the existence of our continents is due. These, in 

 conjunction with the ripple-mark, the foot-print, the impression of 

 rain-di'ops, fuunish us with evidence, that the early condition of 

 land and sea was, in some degree, similar to the present ; at least, 

 that tides and waves, that currents and winds were then in opera- 

 tion, as at present. And the existence of these phenomena points 

 us also to other facts ; for the currents were produced by inequal- 

 ities of bottom, or the proximity of land, as the winds were prob- 

 ably due to inequalities in the surface above the ocean, and rain 

 was only produced by mountains or high lands, which would 

 condense the vapor. 



As a class, all these phenomena adduced, aid us in determining 

 the conditions under which deposits were actually made, while 

 all the subsequent modifications are indicated by other phenom- 

 ena. These, together with the character and condition of the 

 fossils of the strata, may be found important auxiliaries in our 

 investigations, and aid us in determining the great problem of 

 the condition of the surface at remote periods, and the compara- 

 tive extent of sea and land. 



