pkindle.] FORTYMTLE REGION. 55 
the si ream leaves it to cross the flat to the Seventymile is only 120 fee! 
wide. The bed rock is conglomerate, interbedded with shale contain- 
ing many fossil loaves of Arctic Miocene (Eocene) age. The strike 
is N. G0° W., and the dip 75° upstream to the north. The gravels 
are composed of the pebbles found in the conglomerate, fragments of 
the conglomerate itself, pieces of shale and sandstone, occasional 
1 >owlders of quartzite a foot or more in diameter and unlike the pel >1 >les 
found in the conglomerate, and bowlders of conglomerate, which are 
finer grained than that outcropping along the creek, are very compact, 
and contain a larger proportion of chert pebbles. The creek has been 
worked to a width of 100 feet at the mouth for about one-half mile 
upstream. The pay streak is said to have been about 6 feet wide. 
and the total production about $10,000. 
The fall*. — The falls are about 20 miles northwest of Eagle, on the 
Seventymile. Below them the valley of the Seventymile is bounded by 
conglomerate on both sides; above them for a few miles the river flows 
close to the contact of the old metamorphic schist formation and the 
conglomerate; at them the river is cutting the schists and has become 
separated from the conglomerate by a hill of schist and impure lime- 
stone 400 feet high. The falls are only about 9 feet in height. Just 
below them the stream flows through schist walls 20 to 40 feet apart 
and 20 feet high. The strike of the schistosity is about N. 75° E. ; 
the dip 25° to the northwest. Folding has been very close, as is shown 
by the closely appressed minor plications, and* the rocks have 
been much jointed. On the south side of the stream, just above the 
falls, there is a deposit of gravel on the schist 3 to 9 feet thick, covered 
with a few feet of muck. At the point where work was in progress 
the bank is about 10 feet high; a section from top to bottom showed 
2 feet of moss and muck, 4 feet of fine gravel and sand, 1 foot of 
muck and sand, and 3 to 4 feet of gravel. The gravels include con- 
glomerate, schist, vein quartz, limestone, and considerable clay. Pay 
is said to be found all through the lower gravels. 
Three men were working at this locality. A ditch 1-J- miles long 
brings water from Washington Creek to a point on the opposite side 
of the Seventymile, across which it is carried in a canvas hose, s • 
inches in diameter, on a bridge 220 feet long and 30 feet high, to 
another ditch 400 feet in length, whence it is used (PL XII, />). 
During the night the water is run on the muck, sluicing it away, and 
thus preparing the ground for shoveling in. 
Sonickson Greek. — This creek heads in the high ridge about C> miles 
south of Seventymile and enters the river about 2 miles west of the 
fall. In this part of its course it runs close to the southern boundary 
of the valley, leaving on the north a finely preserved Hat a half mile 
in width and 20 feet above the stream. Sonickson is a small creek, 
flowing in a canyon whose slopes exhibit well-defined benching in the 
