MOWER COUNTY. 357 



Devonian limestones.] 



The Devonian Ihtirxtoncs. Beginning with the uppermost of the Devonian 

 strata.we find a fine-grained ilol<nnHi<- limestone, quarried at Le Roy, in the 

 southeastern corner of the county. It is exactly like that seen near North- 

 wood, Worth county. Iowa,* a few mites south of the Minnesota state line. 

 The full thickness of these strata cannot be stated, but about fifteen feet 

 can be assumed for their maximum thickness at Le Roy. They contain 

 stromatoporoid corals, and but very few other fossils. In some quarries a few 

 beds of shale three or four inches thick can be seen between the limestone 

 beds. 



Thomas Rough's quarry is three-quarters of a mile east of the village, and exposes six feet 

 of fine-grained beds that have a perceptible dip toward the northeast. The quarries of Joseph 

 Brevier, of which two are opened, are in the left bank of the Upper Iowa river. The rock here is 

 fine-grained, and in beds from three to six inches thick. On the land of F. Brevier, where the 

 highway crosses the river on sec. 27, can be seen the underlying beds that differ much from the 

 stone quarried at Le Roy. They appear at the spring just below the bridge, and exhibit about 

 two feet of strata. They are granular, vesicular, and when wet rather soft; the upper part being con- 

 fused and indefinite in stratification, in transition from the overlying compact beds and the magne- 

 sian rock seen on Beaver creek in Fillmore county ami at Chester. Iowa. They show a slight dip to the 

 south. The quarry of Widow Cady Palmer is at the road-crossing of the north fork of the Upper 

 Iowa river on sec. 21, Le Hoy. Levi Alsdorf 's quarry, S. E. J sec. 21, Le Roy, shows about ten 

 feet of beds, parted by layers of one to three inches of shale, with a slight dip to the southeast. 

 The quarry owned by the heirs of L. Johnson is about forty rods from the state line, in sec. 35, 

 Le Roy. It is in a lightly timbered tract of country, accompanying the Upper Iowa river, and 

 about ten rods south of the river. The beds rise to within a foot or two of the surface, on the 

 the angle of the river bluff, though the bluffs of the river are not conspicuous, the depth of the 

 valley being only about ten or fifteen feet below the general level, and broad and basin-like. The 

 foreign drift about is light, but some large boulders are scattered about. This stone is light- 

 colored (nearly white), hard and fine, exactly like the Devonian seen near Northwood in Iowa, 

 though in heavier beds than that. It would make a beautiful white marble. It is uniform in, 

 texture, and not in the least porous. With the exception of one or two layers of an inch or two of 

 green clay, the beds are all of this limestone, exposed twelve feet. At Judson A. Palmer's 

 quarry, the rock is overlain by six inches of soil, though a hundred rods from the river. These 

 beds are all badly weathered, so far as opened, and show no important variation from the other 

 quarries ; exposed three feet. Mr. Palmer's other quarry is in the river bluff and has furnished 

 stone that has been burned for quicklime. The stone is the same as that already described. 

 Browne's quarry is also in the bank of the river, but shows only about six feet, though there is 

 every opportunity for opening the beds to a greater depth. There is here a more argillaceous and 

 fissile bed than any in the other quarries. It is about eighteen inches thick. This layer, coming 

 about midway in the quarried beds, facilitates the working of the quarry, but is itself of no value. 

 In the debris thrown out, probably from this layer, a globular mass of Coenostroma was obtained. 

 There is an exposure of the limestone in the valley of the Upper Iowa, near the west line of the 

 S. E. J of N. W. J of sec. 29, Le Roy. There is here a boiling spring, coming out of the rock, in 

 the bed of the creek. The rock is also exposed just over the state line in Iowa, on the Little Cedar, 

 and more particularly at Staceyville, two miles south of the line. 



Underlying the above is a granular, often vesicular, dolomitic limestone. 



*At Xorthwood are numerous walls and foundations built of stone exactly like that of the numerous boulders that 

 are distributed over Kreeborn county and counties further northwest many of which hare been burnt for quicklime. 

 The I .yers an' about fmir inches in thickness but sometimes Rre eight inches, very close-grained, and of a light cream- 

 color Still . in th center of the thick lieds is a hlue spot, indicating the original blue color of the whole Only a small 

 outcrop of these beds oecnrsat Northwood hut three miles farthcrsou h on the shell Rock river, these l<eds appear again 

 and have been opened They are here horizontal and vary from three to ten inche- in thicKness. The only visible fos- 

 fils are badly weathered, and i-how on the outer surfaces They are FnvoMes, Ccenostroma. AcerviUaria, and perhaps 

 one or two other corals. At Beckett s quarry aboul six feet of very hard, fine-grained beds are visible. 



