Allen. 



Omaha 634 miles. 



TnE OVEELAND ROUTE COUNCIL BLUFFS TO OGDEN, 55 



+ 



At Allen station, which is only a section house, the railroad passes 

 from the Steele shale to the Mesaverde formation, which is here 



uptm*ned and dips steeply toward the east. The 



softer layers, consisting of looso-toxtured sandstone 



Elevation 6,601 feet, ^^^j shale, have bccn eroded, loavinor the harder layers 



to form sharp-crested ridges that are prominent along 

 the road for a distance of about 4 miles west of Allen. The Mesaverde 

 hero has its full thickness, whereas at Pine Ridge the upper j)art had 

 been eroded away before the Tortiar}^ beds were laid down upon it. 



Although the Mesaverde farther west is an important coal-bearing 

 formation, httlc coal occurs in it here. A few tliin seams less than a foot 

 thick crop out near the road, but none of economic value have been 

 foimd. The formation is characterized by two zones of hard sand- 

 stone separated by softer beds of shale containing fossil oysters and 

 other shells of marine and brackish-water origin. These softer rocks 

 have been eroded to form the depression which was crossed about 2 

 miles west of Alien, and which contains, north of the track, a small 

 lake fed by sulphur springs at its west end. 



From fhe crested ridses of the Mesaverde formation the traveler 



passes westward over a relatively smooth surface formed on the Lewis 

 shale. The Lewis is a marine shale, somewhat sand}^ in places, and 

 contains hmestone concretions and great numbers of fossil shells, which 

 belong to the Pierre fauna and indicate Upper Cretaceous age. 



Como is a section house on the new cut-off between Allen and Dana. 

 The original hue, now abandoned, was built by way of Carbon, 4 miles 



south of Como. The new hue not only shortens the 

 distance and ehminates sharp curves and heavy 



o^ha'So^miic^^^ gradcs but passes through Hanna, the center of an 



important coal-mining district. At Como the road 



Como. 



is built through a small lake about a mile long, in which arc found 

 great numbers of salamanders that grow to be nearly a foot in length 

 and are locally known as ^'fish with legs." These salamanders are 

 rather common in southwestern United States and in Mexico, where 

 they are used as food. The Mexican name for them is axolotl and 

 the scientific name is Amhhjstoma mavortium, ' 



About a mile east of Como the road passes from the Lewis shale to 

 a younger formation, called ''Lower Laramie/' consisting of soft, 



easily eroded sandstone and shale containing fossil plants and shells 

 of fresh-water invertebrates. West of the section house may be seen 

 the yellow sandstones of the ''Lower Laramie" overlain unconforra- 

 ably by the conglomerate at the base of the Tertiary — the ''Upper 

 Laramie." Thence westward for 5 miles the road is built on con- 

 glomerate, which is well exposed in a prominent hiU to the left (south) 

 of the track. It reaches the coal-bearing portion of the ''Upper 

 Laramie" in the Hanna Basin, a depression formed by mountain 

 uplifts at the beginning of the Tertiary period and filled with con- 

 glomerate, sandstone, and coal-bearing shale. (See table on p. 56.) 



