MOWER COUNTY. 359 



Devonian limestones.] 



leaving the county on the south side of Turtle creek. On the east side of 

 the Cedar river a similar terrace, or bench of more elevated land, skirts the 

 valley through the township of Lyle, bearing away from the river toward 

 the valley of Rose creek, where the limerock is again exposed slightly on 

 the land of Andrew Robertson, sec. '2(5, Windom, in a little valley tributary 

 to Rose creek. The same or similar beds are next seen on the S. W. ^ sec. 

 20, Frankford, where Mr. Aaron Bush quarries them in the valley of Deer 

 creek. Here the rock is parted into blocks that are quarried out without 

 blasting or breaking. They are much faded and rotted hi situ, having over 

 them only a thickness of about four feet of loam. The beds are from six 

 inches to two feet thick, and amount to about ten feet altogether. The 

 stone is very good for all masonry. It is easily dressed and has a yellow- 

 ish buff color. On the S. E. \ sec. 30. Frankford, the same rock was struck 

 in the well of (4. C. Easton, and was drilled into sixty or seventy feet. The 

 abutments of the iron bridge (over the pond) on sec. 20, are from Bush's 

 quarry. The stone is firm and quarried in blocks three feet long and about 

 twenty inches thick. There is another quarry not much worked a short 

 distance below this bridge, in the banks of the Creek. The rock quarried 

 at Bush's appears in the south bank of Deer creek, at Frankford, nearly on 

 the county line, overhanging and perpendicular, in heavy beds from two 

 and a half to four feet in thickness. It is vesicular, as there, and porous, 

 and even cavernous, rough exteriorly, and presents the aspects of the coarse, 

 magnesian beds of the lower Devonian limestones as seen at Spring Valley, 

 containing also the peculiar atrypoid casts known as little titiilen. This is 

 on the land of John Hawkins, Again, on the 8. W. sec. 2, west of both 

 cmssings of Bear creek, similar heavy beds ot magnesian limestone are 

 seen, but nothing can be affirmed of their equivalency with those at Frank- 

 ford. These appear to be overlain by the rusty conglomerate supposed to 

 belong to the Cretaceous. 



The so-called Austin fork underlies the foregoing coarse magnesian 

 si r;ita. This stone, as it appears at Austin, is a fine-grained sandrock, or 

 shaly sandrock. that cracks like some shales after exposure to the weather 

 In some places, further down the river, it is a fine, calcareous sandrock. 

 The texture of the stone itself is close and the grain is homogeneous. Some 

 slabs have been sawn for bases to tombstones. It is more safely sawn to 



