SOME GEOLOGICAL FEATURES OF SOUTHERN KANSAS. 681 



While the ironstones are exceedingly abundant, they usually contain so 

 much silica that they could probably not be profitably worked for their iron, even 

 if coal were at hand. Some specimens, however, are nearly free from silica. 

 These bear a striking resemblance to bog-iron ore, and it is possible that, could 

 coal be discovered in close proximity, they might be found in some sections in 

 sufficient quantity and purity to pay for working. 



Besides the concretions of iron and silicate, others of lime are common in 

 much of the sandstone. These usually have one side convex and covered with 

 nodular protuberances, the other showing one or more concavities lined with 

 small crystals of calcite. 



Whik the concretions of iron will probably yield no one a fortune, ai d we 

 should not look even for farthings in limestone concretions, these plain aggrega- 

 tions of common minerals are promissory notes to the farmer that should make 

 his face beam with joy whenever his eye falls upon them. They are as good to 

 him as gold certificates, for they tell him of unstinted gold which they have 

 spread before him and which shall be his for the stooping and taking. 



Concretions are form:;.' — often about an organic nucleus — where their com- 

 ponent originally existed in small quantities diffused through the rock in which 

 they occur. Their rationale is little understood, but that such are the conditions 

 of their formation is a matter of observed fact. Lime and iron, then, in a diffused 

 state and in small quantities once existed in this sandstone, the former probably 

 mingled to some extent with traces of phosphates and sulphates. It is plain of 

 the iron, as shown by the color of the sandstone, and is doubtless equally true, 

 if less evident, of the lime and other mineral constituents, that they are but partly 

 expressed by these concretions and that they are therefore still diffused through 

 the strata to greater or less extent, and so in the soils that have resulted from its 

 decomposition. 



If to such a soil have been added, as is here probable, small contributions 

 from the gypsiferous clays that once overlaid the sandstones, and still later from 

 the tertiary, the result would be a soil of unsupassed fertility and adapted in the 

 highest degree, by reason of the porosity and capillarity of the sand, to raise large 

 aver'ge crops with a small average rainfall, and to withstand drouth when other 

 soils wruld fail. 



Such is the soil of the Dakota belt, at least in southern Kansas. Nor could 

 a better combination of ingredients be found for road-beds. I have driven be_ 

 tween Harper and Medicine Lodge in sunshine and in rain, and have found the 

 roads neither dusty nor muddy. Indeed dust and mud are well nigh impossible 

 in such a region, except where some "settle" has accumulated an undue pro- 

 portion of lime and clay, and these spots are small and the mud shallow. 



The only really bad portions of the roads are found along the streams where 

 the waters have washed out the lighter ingredients of the soil, leaving the sand. 

 Here, as in all loose sand the traveling is heavy. 



The streams of this region are mostly without appreciable banks, the larger 

 ones, and many of the smaller, having their little sand-hills, and thus aping the 



