Klamath Mowiiains, California. — Hershcy. 237 
Along the eastern border, near the schist contact, the Pale- 
ozoic strata resemble the known Devonian on the opposite side 
of the schist belt as in Shasta county, particularly in their ex- 
tremely cherty constitution, and while no fossils have been 
found to fix positively the presence of Devonian rocks in the 
western belt, it is safe to assert that in traveling from the east- 
ern schist belt westward, one traverses progressively (except 
for a minor folding) higher members of the Paleozoic series 
until the Mesozoic rocks are reached. The argument that I 
wish to draw from this premise is that practically the entire 
thickness of the Paleozoic rocks is present under the Mesozoic 
belt, and that along the axis of this belt, where the Bragdon 
slate is at least 1000 feet thick, and the Clear Creek volcanic 
series probably of like thickness, the base of the Paleozoic 
rocks where they rest on the schists, must be at least 7000 feet 
beneath the present surface; probably it is much deeper. 
Where the Trinity river crosses the axis of the trough, near 
Hawkin's Bar, the schists must be depressed to not less than 
5500 feet below sea-level. There is no reason for believing 
that the axis of the trough rises materially to the northward 
or southward within the limits of the area under discussion. 
The schists in the belt on the east rise to an altitude of 8500 
feet above sea-level and those on the west reach nearly or quite 
6000 feet. It is very likely that were the base of the Paleo- 
zoic rocks restored to its position over the crests of these two 
schist ridges, it would be far above any elevation now reached 
by these schists. Therefore, any calculation of the depth of 
the trough based upon the present highest poiftts of the border- 
ing schist ridges will be a perfectly safe one and probably fall 
far short of the reality. 
Generalizing broadly, I shall say that this western geosyn- 
cline of the southern Klamath region is a trough from thirty- 
five miles wide in the south to fifty miles wide in the north, 
and 11,500 feet deep relative to its- western edge and 14.000 
feet deep relative to its eastern edge. 
The eastern geosyncline is even broader and pcrhai)s deep- 
er than that just defined. Only its western half properly be- 
longs to the Klamath region and extends from the crest of the 
eastern schist ridge of Trinity county to the Big Bend region 
of Shasta county. It includes all that portion of the Klamath 
