418 A. Winchell — Trend and Crusted Surplusage. 



meridionality and supply also an adequate supplement of crus- 

 tal surplusage to meet the demands of orogenic phenomena. 



1. I assume that meridionality in the earth's surface features, 

 will be granted. There are, indeed many transmeridional fea- 

 tures ; but they have arisen from geological actions compara- 

 tively late. The oldest mountain chains and continental lines 

 tend distinctly toward north-and-south trends; and this predis- 

 position has given direction to many trends of later geological 

 appearance. This is the fundamental impress received by the 

 earth's crust. Evidently, it belongs to a primitive formative 

 stage. We must seek for the cause in the early periods of in- 

 crustation. 



Now, let us consider lunar-tidal action during those periods. 

 This is a cause to which I appealed in a work published as long 

 ago as 1870, and in periodical literature as early as 1858. Were 

 the moon's tidal efficiency no greater then than at present, its 

 deformative influence must have been experienced by the earth. 

 If ever our planet was a molten sphere, a tidal prolateness 

 stretched its axis in the direction of our satellite ; and the axial 

 revolution of the planet changed constantly the portion of mat- 

 ter tidally elevated. As the matter of the molten earth pos- 

 sessed some degree of viscosity, there was then, as always, a 

 lagging of the tide, and the moon exerted that action now so 

 well understood, which antagonizes the planet's rotation. After 

 incrustation had begun, this action was not materially dimin- 

 ished. The greater viscosity (or partial rigidity) of the crust 

 would, indeed, tend to shorten the prolate tidal axis; but, in 

 proportion to increase of the index of viscosity; the lagging 

 of the tide would also increase and thus augment the moon's 

 retral action on the tidal protuberance. But the tide continued 

 to rise and fall ; and would have continued if the earth had 

 become solid granite. Tidal movements of the crust must 

 result in fractures, friction and displacements. 



By as much as the moon's tangential pull on the tidal mass 

 was capable of antagonizing the earth's rotation, by the same 

 it tended to displace the tidal mass toward the west. There 

 must have been some retral slipping. The power which could 

 deform a planet could move a raft of frozen matter floating on 

 a molten liquid, especialty if floating in the midst of a hemis- 

 phere of fragments more or less discontinuous. This westward 

 impulse was continually repeated on each meridian as it came 

 in succession into the position of the tidal crest. The effect 

 was such as could result from a westward push of the forming 

 crust, applied successively over the whole surface within the 

 parallels limiting the tidal disturbance. The slight backward 

 slipping of every part in succession of the tidally moved zone 

 must have developed, in the growing crust, internal structures 



