GEOLOGICAL SUEVEY OF THE TEERITORIES. 95 



Near, the crossing of the Big Laramie Eiver, we see on our right the 

 red beds, which are somewhat marked; we can follow these up to the 



foot of the by their peculiar brick-red color. Here come the 



Cretaceous rocks, especially the upper members of the group. Very 

 soon after crossing the Laramie Eiver they continue .to a point about 

 five miles east of Coino, where the Tertiary beds overlap. Isolated 

 patches of Tertiary appear before reaching Rock Creek. At the quarry 

 the black slates of jSTo. 2 are quite conspicuous, but the sandstones which 

 are transported to Laramie and to Cheyenne are most probably Lower 

 Tertiary. They are filled with fragments of stems and leaves, some of 

 which are distinct enough to determine. 



The surface of the country for the first 25 miles after leaving Laramie 

 westward presents a cheerful appearance. The basis rocks are com- 

 posed of the arenaceous marls and clays of the Upper Cretaceous period, 

 and these, yielding readily to atmospheric agencies, are worn down so 

 that all the hills and ridges are smoothed off and rounded, and covered 

 with a good growth of grass. Indeed, the county is in striking con- 

 trast with that farther to the west. 



After leaving Cooper's Lake Station, we begin to approach the black 

 clays of No. 2, and then beyond the Tertiary beds; and from thence to 

 Bitter Creek we pass over one of the most barren, desolate, forbidding 

 regions I have ever seen west of the Mississippi. 



From Cooper's Lake Station to a point about 35 miles, the black 

 plastic clays of the Lower Cretaceous prevail, giving to the surface of the 

 country the usual dark, gloomy, sterile appearance. 



Very little vegetation is to be seen ; no timber ; and the prevailing 

 shrubs are the greasewood and sage. 



The waters of all the streams are full of alkali, and the standing 

 liooLs have the color of lye. 



Between Lookout Station and Eock Creek are some cuts through the 

 rocks, which revealed many beautiful Cretaceous fossils, as Ammonites^ 

 Bac'uUtes, Inoceram.nSj Belemites, &c., all of which are characteristic of 

 the chalk i^eriod in the West. 



From a point about 10 miles east of Como to Saint Mary's Station, a 

 distance of about 50 miles, the Tertiary formations occupy the country 

 with the peculiar sands and sandstone and clays, and numerous coal- 

 beds. The most marked development of the coal-beds is at the Carbon 

 Station, about 80 miles west of Laramie Station. The rocks incline 

 nearly southeast, or south and east. Three entrances have been made to 

 the mine, and the bed is nine feet thick. The openings follow the dip, 

 and consequently descend. The mines are about 3,000 yards from the 

 railroad, but a side track has already been laid to them. More than 1,000 

 tons of coal have already been taken, and the Union Pacific Eailroad 

 Company are ready to contract for any amount that can be supplied to 

 them. The coal at Carbon is of the best quality of Tertiary splint, very 

 compact and pure. It is not as hard as anthracite, but the miners in- 

 formed me that it was more difficult to work than the bituminous coals 

 of Pennsylvania. There are many old miners here who have spent their 

 lives in the mines of Pennsylvania and England, and inform me that this 

 coal is superior to any of the bituminous coals, andranksnest to anthra- 

 cite. It is used to a great extent on the locomotives, and the engineers 

 speak in high terms of it, while for domestic purposes the universal 

 testimony is that it ranks next to anthracite. Over the coal there is 

 what the miners call slate ; this is somewhat earthy, breaking off into 

 slabs, showing woody fiber, and much of it looking like charred wood or 

 soft charcoal. As we pass up fragments of deciduous leaves are seen 



