47 THE POPULAR SCIENCE MONTHLY. 



if not the why, of all things terrestrial. Here is a corner of the world 

 in which the evidences of change of transition are so patent that a 

 glance reveals them to the dullest beholder. It is as if Nature were 

 here trying to impress upon her children a great object-lesson, as if 

 the universal Dame had said : " Behold ! Look ! Here have I stripped 

 all the hills and laid bare all the valleys, that you might learn my time- 

 honored methods, and once for all see something of how worlds are 

 made." No man would say, as he looks for the first time out over 

 these naked hills : " Such have they ever been ; such shall they always 

 be." By no means. These, at least, are not the "everlasting hills." 

 Here is transition. Now, transition is to the student a word of magic 

 sound echoing the past, prefiguring the future. Let him but behold 

 any of Nature's processes in intermediate stage, and mystery as to 

 mode and method vanishes ; the solution is easy. 



But, now that our object-lesson is before us, what can we learn 

 about it ? Let us look again from the top of the butte, this time for 

 instruction rather than for pleasure. See, there the river winds a 

 silver thread, shut in by long lines of banded bluffs. Into the river- 

 valley principal ravines debouch, others into these, and so on to the 

 very base of the bluff on which we stand. And now, you say, the 

 problem is solved ; the river is the outlet, and all these strange phe- 

 nomena are due to surface-drainage. Here is the water-system, and 

 here are its effects. But this answer can be but part of the truth, else 

 why are no Bad Lands seen along the Desmoines or the Tennessee ? 

 Why are they not of universal occurrence ? Besides, the beds of all 

 these ravines are, for the most part, flat and level as a floor, scantily 

 covered with short grass, or white with sage-brush [Artemisia). Only 

 here and there a gully without water, or perchance, in some larger 

 ravine, we may find a tiny, scarcely flowing streamlet, brown with 

 alkali. Manifestly the river-system accounts for the general features 

 of the country, but not for that which is peculiar. But let us look at 

 the problem in another way. Let us begin at the bottom of these hil- 

 locks, at least as low down as we may come, and study for a moment 

 the hillocks themselves. 



We have already incidentally noticed the uniform stratification 

 which characterizes the whole country, and is revealed by the banded 

 appearance of the hills. At the base of one of these hills we may 

 find (Fig. 1) a stratum of pale, yellowish clay. Just above, and per- 

 fectly conformable, is a layer of lignitic coal, inferior to soft coal, of 

 a deep-brown color, rapidly crumbling on exposure to the air, and 

 even, when in sufficient mass, liable to spontaneous ignition. Over- 

 lying the coal is another bed of clay of an ashy hue, containing more 

 or less sand in composition. Next comes a layer in which sand pre- 

 dominates, a distinct gray in color ; then a bed of clay of a bluish 

 tint, another layer of coal, a layer of yellow clay, a stratum of very 

 soft sandstone, another bed of clay, and then a foot or two of reddish- 



