244 GEOLOGICAL SURVEY OF THE TERRITORIES. 



hieroglyphics. The engraving of the child's foot is cut in its deepest 

 part, three-fourths of an inch into the hardest rock, and for fidelity to 

 nature it would do honor to the work of a Greek artist. Previous to my 

 discovery ot this relic of the past (1869), no one in that region had 

 heard 'of its existence. It may have been the work of the mound-build- 

 ers, as their peculiar pottery and mounds are found near by, but what 

 implements enabled them to carve these symbols in this hard rock, as 

 well as the purpose of such a monument at such a place, will probably 

 always remain a mystery. 



South of the Platte the Drift creeps to the surface on some of the hill- 

 sides of Lancaster, Saunders, Saline, Butler, Gage, Seward, Johnson, 

 Pawnee, and Jefferson Counties. In fact, there are few counties in the 

 eastern part of the State where the Drift is not occasionally exposed by 

 denudation. Four miles northwest of Nebraska City, on the farm of 

 Hon. J. F. Kinney, is a granitic bowlder as large as a small house, on 

 whose top smooth holes have been worn by the Indians in grinding or 

 pounding corn. This bowlder is imbedded in a Loess deposit, through 

 which it extends from the Drift below. Here, as in most other regions, 

 the Drift varies a great deal in character. As already intimated, it has 

 here been so modified by subsequent lacustrine agencies as generally to 

 be capable of high cultivation. Eecently I have made a special exam- 

 ination of the modified Drift in Johnson County. Where the ground 

 was covered with pebbles, the spade showed that the soil beneath was 

 composed largely of Loess materials, mingled with Drift sand and clay, 

 and organic matter. Here it is often in layers, showing that it is gen- 

 uine modified Drift. This modified Drift soil, during the last season, 

 where it was well cultivated, yielded sixty bushels of corn to the acre. 

 It is only inferior, if inferior at all, to the Loess, which will be considered 

 in the next section. Where this Drift is the purest, it is composed of 

 bowlders, some of which are of large size, pebbles, gravel, sand, and a 

 small per cent, of alumina. In places the Drift contains considerable 

 lime, which was, no doubt, produced by the disintegration during glacial 

 times of the Niobrara division of Cretaceous rocks. Sometimes frag- 

 ments of these Cretaceous rocks are found in the Drift. Generally the 

 pebbles and bowlders are composed of the primary rocks, such as 

 quartz, quartzose, granite, greenstone, syenite, gneiss, porphyry, actino- 

 lite, &c. Occasionally the near presence of the Drift is indicated by 

 large bowlders sticking up through soil composed of very different mate- 

 rial. In such cases I have learned by experience to look for the modi- 

 fied Drift which is so valuable in the agriculture of this State. In the 

 few localities where all the finer matter has been removed by water 

 agency, numbers of the different forms of variegated agates, carnelians, 

 jaspers, sardonyx, onyx, opals, and petrified wood, &c, are found. Agates 

 and petrified wood are specially abundant. The latter is found almost 

 in every exposure of the Drift. Some of the agates vie in beauty with 

 those obtained from the most celebrated localities in the mountains. 

 Judging from the remains of the matrix still attached to some of them, 

 they were originally formed in the primary rocks, from which they were 

 separated by the disintegration to which they were subjected by the 

 wear and tear of the elements in glacial times. 



The scratchings on top of the rocks along the Platte and other rivers 

 where I have been able to examine them, indicate that the general 

 direction of the glaciers was from 19° to 27° east of south. The only 

 exception to this direction that I have found was in Stout's stone-quarry, 

 twelve miles southeast of Lincoln, on the Nebraska Bailroad, where the 

 motion seems to have been 13.5° degrees east of south. 



