154 LEWIS G. WESTGATE AND E. B. BRANSON 
in furnishing the material to the present deposit. The deposit 
seems to be due to aggradation by the earlier Twin Creek. 
A second gravel flat tops Table Mountain south of Lander, 
south of the Big Popo-Agie, at an elevation of 7,200 to 7,300 feet. 
A slide on the north side of the Mountain shows 175 feet of gravels 
resting on a somewhat uneven surface of Chugwater and later beds. 
In the section the bowlders usually reach a size of one to three feet, 
but many are over five feet and one was seen ten feet in diameter. 
The bowlders are well rounded, closely packed, and much weathered 
and consist of Paleozoics and crystallines. The filling between the 
bowlders is a sort of granitic sand, which seems to have come from 
the rotting of the bowlders. From a little distance the deposit 
appears to be indistinctly stratified. ‘There is no evidence that 
it is not stream-made, though the size of the bowlders has been 
thought to indicate ice-action. The bowlders, however, are not 
larger than those found in arid regions at the head of alluvial fans 
some distance out from the mouth of the feeding cafons. The 
slope of Table Mountain is estimated at twenty-five feet per mile 
away from the mountain. The slope seems too gentle for the accu- 
mulation slope of such coarse materials, and the fact that the sur- 
face of Table Mountain is not a plain, but is trenched by shallow 
valleys indicates that it is not original but a cut surface. The Ten 
Sleep sandstone ridge to the west is cut away to a level correspond- 
ing to that of Table Mountain, as if a rather broad valley had here 
opened out from the range. 
A similar deposit of coarse gravels forms a high flat near the 
range on the north side of the North Fork of Little Wind River 
(Fig. 3, B), at an elevation of from 7,445 to 7,700 feet. These 
gravels have a thickness, at the south end of the exposure, of 250 
feet, and lie on the inclined Chugwater beds. They consist of 
well-rounded bowlders up to six feet in diameter, closely packed and 
thoroughly rotted. Stratification here is distinct and several 
layers of sand and fine gravel, up to four or five feet in thickness, 
occur in the deposit, showing that it is water-laid. The surface 
relations of the deposit are shown in Fig. 7, where A-B is the flat 
under consideration. Its surface is nearly level, and it is cut by 
D-E, a more irregular plain which drops away toward the Wind 
