356 THE GLACIAL LAKE AGASSIZ. 



shown liy wells. On the north line of section 20, and again in the north 

 part of section 17, it is intersected by branches of Cart Creek, which occupy 

 valleys about 40 feet deep and an eighth to a (quarter of a mile wide. 

 Brush and scattered trees grow in these valleys and on the area between 

 them. Toward the east a descent of 30 or 40 feet is made within the first 

 half mile; westward there is only a slight ascent, to about 1,200 feet, in 1 

 mile; then a more considerable slope, covered with woods, rises 20 to 40 

 feet to the base of the "second mountain," on or near the town.ship line. 



In the west part of section 8, and again near the northeast corner of 

 section 6, Thingvalla, this beach is intersected by the head streams of Wil- 

 low Creek, in valleys about 35 feet deep. On the north lino of sections 5 

 and 6 of this township the fourth and third Herman beaches are merged 

 in an undulating tract of gi-avel and sand a half mile wide, which rises 

 from 1,160 feet on the east to 1,184 feet on the west. A well on the west 

 pai-t of this belt found the beach deposit 6 feet thick, underlain by till, 

 which forms the slightly ascending surface next west. 



Base of the second Pembina Mountain, in the east half of section 31, 

 township 161, range 56, 1,235 feet at the south to 1,220 feet northward, 

 coinciding nearly with the upper Herman shore of Lake Agassiz. William 

 Crombie's well, 24 feet deep, near the center of section 30, situated about 

 50 feet above the Tongue River, a few rods back from the verge of its north 

 bluff, was soil, 2 feet; gravel, nearly all Cretaceous shale, 8 feet; underlain 

 by gravel, nearly all granite and gneiss, with scarcely any intermixtm-e of 

 shale, containing pebbles and cobbles up to 4 inches in diameter, 14 feet, 

 yielding a permanent su])ply of water. This well is close to the base of 

 the "mountain," at an elevation of about 1,230 feet. Its bed of granite 

 gravel appears to be the upper beach, the overlying shale gravel being a 

 delta deposit brought by the Tongue River. 



Surface at Young post-office, in the northeast corner of the southwest 

 quarter of section 32, townslnp 161, range 56, 1,192 feet. The well here, 

 14 feet deep, is wholly stratified gravel and sand, being a beach deposit of 

 the second and third stages in the Herman series. Thu-d beach, about an 

 eighth of a mile east of Young post-office, a broad ridge of sand and fine 

 gravel, a few feet above the laud on its west side, crest, 1,187 feet. Fourth 



