Hayclen.] 



54 



[February 19, 



50 miles, all tlie unclianged rocks of older date ; but a careful study of tlie 

 eastern flank, from Red Butes to Long's Peak, will reveal all the forma- 

 tions that are known to exist in this part of the west, inclining from the 

 sides of the granitic nucleus at various angles. 



The railroad then for 40 miles passes over and cuts through a great 

 variety of Syenites ; some compact, beautiful building stones, almost 

 equal to the Scotch lyenites, but the greater part ferruginous and easily 

 disintegrating on exposure.* 



Fig 6. 



On the west side of the Laramie range, we pass across the upturned 

 edges of the counterparts of the various formations seen on the eastern 

 slope. From Laramie city to Salt Lake, formations of different ages con- 

 tinually appear and disappear. The Cretaceous formations occupy the 

 country for 60 miles from Laramie city nearly to lake Como. 



Genuine Jurassic beds, with characteristic fossils, are here exposed for 

 a short distance, in an anticlinal valley, along which the railroad passes. 

 Belemnites densus are in great numbers. 



Cretaceous beds mostly ISTo. 2, appear again west of Como. 



Miocene coal beds overlay the cretaceous, just before reaching Carbon 



* These syenites weather into most beautiful forms resembhng gigantic ruins, so that they 

 have sometimes deserved their common appellation, of broken down temples, castles, &c. The 

 sketch, (Fig. 5,) shows well the peculiar features which these piles of rocks assume through atmos- 

 pheric influences. It is engraved from a photograph of ascene on the Laramie range, taken by Mr. 

 Carbutt, photographer, of Chicajco, Illinois. 



