28 BIG SPRING PRAIRIK. 



an extent, that the mesophytic condition was gradually 

 reverting to the hydrophytic condition again. 



As evidence of the settling of the soil and the ex- 

 tent of the settling, we would call your attention to 

 figure 1 which shows a large bowlder resting on drift 

 clay. The location of this bowlder is indicated on the 

 Map. The dark band along the side of rock near the 

 top marks the old marsh level; the shorter band of dark 

 and light streak near the base of rock was exposed by 

 prairie fire which burned the soil several years ago. 

 The picture does not do justice to the real appearance 

 of the rock. The portion above the upper band is old 

 and exceedingly weatherworn, and partially covered 

 with mosses. The portion below the upper band has a 

 clean, bright surface as if it had been more or less acted 

 upon by humic acids. The difference in the appear- 

 ance of these distinct areas is far more striking on the 

 bowlder than in the picture. The decrease in level of 

 this part of prairie is thus shown to be about 2.^ feet. 



Mr. Peter Brayton states that when a young man, 

 he was one day walking across prairie not far from the 

 edge, a short distance north of New Road 2, which 

 crosses his farm. The ground was wet and springy. 

 At each step, his feet would sink into the muck. He 

 happened to step upon something solid. Upon inves- 

 tigation, he found it to be a bowlder, whose top was 

 slightly below the surface. In 1899, the bowlder was 

 projecting about 20 inches above the surrounding level. 

 This seeming elevation of bowlder, and actual settling 

 of soil occurred after artificial drainage was introduced. 



The old settlers are quite unanimous in their testi- 

 mony, that a person could shake many square rods of 

 ground by jumping upon one of the "bogs" as they 

 called the ''sedgy hummocks" projecting above the 

 general level; and also, that portions of prairie muck, 

 seemed to be quite deep as poles could be thrust vertic- 

 ally into the soil to the depth of ten feet or more. At 



