312 GEOLOGY. 



are. some of the finest massive limestones in the State. The upper 

 surface, where the superficial deposits aie removed, are worn as 

 smooth as mirrors, and exhibit the parallel striae so characteristic of 

 glacial action. Unfortunately, the great thickness of the superfic- 

 ial deposits here makes these quarries expensive in working. At 

 La Platte, near the line of the Burlington & Missouri Railroad, 

 there is another remarkable quarry of fine-grained, slightly silicious 

 limestone. It contains innumerable impressions of fusulinas. The 

 government architects selected the stones from this quarry with 

 which to build the United States post-office and court house in Lin- 

 coln. It successfully stood the severest mechanical and chemical 

 tests. Farther up the Platte and on its north side, opposite South 

 Bend, W. B. Stout, Esq., has opened a new quarry during the last 

 year. Here occur several strata of unusually massive limestone, 

 one, of which, eighteen inches thick, is partially oolitic and partly 

 filled with fusulina. Near the middle there is a layer of intensely 

 liard nodules of silicious matter. The limestones in this quarry are 

 of exceptional purity. They take a very fine polish. On the 

 whole, it is the best stone quarry that I have yet visited in the 

 State. Some of the piers in the new railroad bridge at Plattsmouth 

 were constructed of this stone. The contractor' is also using it in 

 the construction of the new capitol wing at Lincoln. Other fine 

 quarries are also opened on the south side of the Platte in strata of 

 a similar character. East of Lincoln, on the Nebraska railroad, at 

 Syracuse and at other points, there are quarries of impure, variously 

 colored limestone of considerable thickness, from which immense 

 quantities of building stones have been obtained. From these 

 quarries and from similar ones on the Atchison & Nebraska Rail- 

 road, a little southeast of Lincoln, the*stones were quarried for the 

 State penitentiary. 



The Cretaceous rocks of Nebraska also furnish a large quantity 

 of excellent building stone. Those of the Dakota Group are mostly 

 silicious. They are of all shades of yellow and brown, sometimes 

 approaching to a cream color and white. They furnish the hardest 

 and the softest stone in the State. The softer varieties are unfit for 

 building stone. Large quantities, however, are a medium between 

 the two extremes, and are very valuable for smaller structures, 

 owing to the ease with which they can be quarried and dressed. 

 In Dakota County, in this. group, occurs the intensely hard quartz- 

 ite which has been used in Sioux City, Iowa, for the foundation of 



