Douglass: A Geological Reconnaissance. 217 



After ascending a branch of the Sweet Brier the railroad enters the val- 

 ley of the Big Muddy, another branch of the Heart River. In this region 

 the outcrops are mostly shale with bands of l)rownish sandstone. 

 There are occasional dumps where coal mining or prospecting has 

 been done. Here too are occasional patches of glacial drift. Again 

 near Dickinson the railroad follows the course of the Heart River. In 

 the vicinity of Dickinson, a neat and thriving city of the prairie, the 

 country is a somewhat uneven plain with higher buttes projecting 

 above the general level. These buttes show that the ancient level of 

 the country has been considerably lowered by erosion, leaving only 

 weathered monuments of its former elevation. Here we see no folds 

 in the strata but the land was uplifted in a mass over a great area, so 

 that the strata appear to the eye to be almost perfectly horizontal as 

 it does until we enter Montana ; then, as we go farther and farther 

 westward, we see more and more evidences of elevation and disturb- 

 ance of the strata until we enter the mountains. 



The rocks in the vicinity of Dickinson represent two entirely dis- 

 tinct epochs, which were separated by vast periods of time, but this 

 does not appear on a casual examination. They represent Early and 

 Middle Tertiary. The greater portion of the rocks of this region, 

 and probably of the larger part of western North Dakota, are of Fort 

 Union (Early Tertiary) age, but the "Little Bad-lands," about 

 twelve to sixteen miles southwest of Dickinson, are composed of White 

 River deposits. These will be described later. Probably some of the 

 surface deposits west and northwest of Dickinson are also Lower White 

 River, but this is not yet quite certain. 



At Dickinson the altitude is 2,405 feet; at Mandan near the Mis- 

 souri River it is 1,664 feet ', so we are now 741 feet higher than when 

 we were at the latter place. From here the elevation increases rapidly 

 to Fryburg which is 363 feet higher. From near that place there is a 

 rapid descent of 500 feet to the Little Missouri River. 



The Little Missouri Bad-lands. 



In the vicinity of Fryburg, as the train passes through a cut, it is seen 

 that the rock is soft, is arranged in layers, and contains hard concre- 

 tions. At a little distance, on a flat sparsely covered with sage-brush 

 and grass, are peculiar-looking bare mounds, which resemble stacks of 

 hay. Suddenly again the train dives into a cut, and, with the eye one 

 follows a layer of coal, which seems to glide along for a moment and 



