GEOLOGICAL SURVEY OF THE TEREITOEIES. 301 



raj)iclly disappeariug as we more westward. As we approacli Hobart 

 Station we euter upon a heautiful imdnlating prairie, with a dark, rich, 

 surface-soil, but I noticed here that it is underlaid with a heavy gravel- 

 deposit, which even a single farrow of the plow exposes to view. As 

 we move on the suri^ce becomes slightly more rolling, not broken, but 

 gracefully rounded into hillocks, ridges, and valleys, with here and 

 there groves of oaks on the hillocks and along the banks of the streams. 

 We ai-e now in that section which I have heretofore spoken of as being 

 the prettiest portion of the State, a description of which need not be 

 repeated here. This beautiful undulating prairie-belt, with its green 

 sward, occasional oak groves, (but these gradually disappear after we 

 l^ass Detroit Lake,) and numerous clear lakelets continue until we begin 

 to descend the divide into the valley of Eed Eiver. The soil is a rich, 

 dark loam ; the subsoil appears to be composed generally of gravel and 

 clay, with a marly appearance, mixed with bowlders, the former decreas- 

 ing and the latter increasing — in proportion — as we move westward. 

 The bowlders are mostly gray or red granite, though some of other 

 rocks were seen. 



I may remark, in passing, that I noticed the cuts through this hilly 

 portion very carefully, to see if there was any evidence of stratified 

 rocks or rocks of any kind in position ; but no sign of such rocks were 

 seen. At some points there are large accumulations of bowlders, but all 

 theSe hills and the entire surface-material for a considerable depth are 

 evidently drift. 



The descent to the valley of Eed Eiver is very gradual along the line 

 of the road, but from the valley it is very apparent, rising up in the 

 form of a sloping bluff. It is unnecessary to repeat the desc»iption of 

 this valley ; the surface-soil is black muck some 4 to 6 feet deep, the 

 first 2 feet being filled with a matted mass of grass-roots; the subsoil, 

 as will be seen from the following record of the boring for an Artesian 

 well at Fargo, is blue clay, which is very tenacious. The margins of 

 the streams in this valley are lined with a narrow strip of timber, chieily 

 oak, with some elm. 



The following is the record of the boring of the Artesian well at 

 Fargo, so far as it had peneti*ated at the time I last visited that point, 

 (September 3, 1872 :) 



Feet. 



Soil 3 



White and yellow (or drab) clay 50 



Fine dark clay 42 



Small stone and gravel ,..^ 10 



Hard clay (" hard pan ") mixed with gravel and bowlders 115 



Soft, dark-blue shale 32 



Coarse saud-rock (i 



Soapslone 4 



After piercing the sand-rock water rose to within some 10 or 12 feet 

 of the surface, with an apparently good supply. The depth of the well 

 at that time was 262 feet, and the boring had stopped with little pros- 

 pect then of being continued, as Mr. Barker, superintendent of the work, 

 thought it useless to go farther, it being his opinion that the next rock 

 will be the igneous or metamorphic. As Vv'ill be seen from this, one 

 drawback in this rich valley is the difficulty of obtaining a supply of 

 water. 



The next line passed over in Minnesota was that leading from Saint 

 Paul to Brgckenridge — a branch of the Saint Paul and Pacific — a distance 

 of two hundred and seventeen miles. The following is an abstract of 

 the notes taken at the time I passed over this road : 



