J. LeConte— Formation of the Coast Range of California. 297 



ease with which isomeric changes may be brought about. If 

 murexide be ammonium purpurate, the formula might perhaps 

 be changed to the form in No. 2. 



While the views above stated as to the structure of the 

 numerous and interesting compounds derivable from urea and 

 uric acid are liable to objection at sundry minor points, and in 

 several instances other arrangements of the elements might be 

 adopted without interference with the main idea, I believe 

 that on the whole the constitutional formulse set forth in this 

 paper more nearly represent the present state of our knowledge 

 of this group than any others which have been proposed, and 

 especially possess the advantage of better explaining the chem- 

 ical character or function of the substances referred to,* while 

 at least equally well exhibiting the nature of the changes by 

 which they are produced from each other. 



University of Virginia, Nov. 4, 1875. 



Art. XXXVIL— On the Evidences of horizontal crushing in the 

 formation of the Coast Range of California; by Joseph 

 LeOonte. 



[Read before the National Academy of Sciences, November, 1875.] 

 It will be remembered that in a former paper "On the 

 formation of the greater inequalities of the earth's surface,"'! 

 I sustained the view that mountain ranges are formed wholly 

 by a yielding of the crust of the earth along certain lines to 

 horizontal pressure ; not, however, a yielding by bending of 

 the crust into a convex arch, filled and sustained by a liquid 

 beneath, as has been supposed by some ; but by a crushing or 

 mashing together horizontally of the whole crust, with the 

 formation of close folds and a thickening or swelling upward 

 of the squeezed mass. I believe the structure of all mountjiin 

 ranges, in which the stratification has not been obscured by 

 nietamorpbism, would demonstrate this mode of formation. 



I have long thought that the Coast Range in this vicinity is 

 peculiarly adapted to exhibit in its structure the mode of its 

 lormation. It is destitute of granite axes, and it has been but 

 little, in many places not at all, changed by metamorphism or 

 overlaid bv igneous ejections. A good section ought to clearly 

 reveal its structure and its structure ought no less clearly to 

 reveal the mode of its formation. 



W ith this conviction, on the 5th of January last, m company 



>> * •^^? formulae of Baeyer (in common with all 



bamide) seem to fail in securing this advantage, 



same sort of view of the ureides as that above stal 



t rhia Journal, III, vol. iv, pp. 345 and 460. 



