Geology of Puyet Sound Basin. — Kimball. 315 
point, some of which, incidental to a number of oscillations of 
level, will presently be indicated. 
Into the interesting field of inquiry suggested by the pre- 
ceding remarks, it will be impracticable to enter far for want 
of close observation of the drift phenomena in the Chehalis 
watershed, and still farther to the south. The present low 
elevation of this watershed is indicated b}^ altitudes of culmi- 
nating points as follows: Tenino 302.5 feet, Roy, 338, Ehiia. 
92. The parting oi' the sound and Chehalis (Grey's harbor) 
waters may be delineated on the map by a single stroke of the 
pencil. Whether the latter river and harbor may not iiave af- 
forded such an outlet — follows as a natural inquiry from the 
suggestive topography of the watershed as graphically exhib- 
ited by certain unpublished surveys of the Northern Pacific 
Railwa}'^ Co., as well as from well recognized drift phenomena 
not inconsistent with the development of a terminal moraine 
coincident with the summit of the same watershed. 
The kame-like gravel mounds near Tenino rise from a field 
of horizontal silts. Other lacustral, prairie-like surfaces in 
the same region are still characterized by retreated lakes. 
A lignite-bearing sandstone formation in low and gentle 
undulations comes to the surface in the Chehalis valley, con- 
stituting the solid border of the sound, as previously desig- 
nated. An interesting feature of this formation is its wide- 
spread alteration for a depth of several feet, beneath a thin 
cover of soil, into a non-silicated aluminous laagnetite.* 
To whatever degree the post-Cretaceous movement was ele- 
vatorj' in the border region of the sound, it doubtless ended 
in resultant relative depression of the sound axis. Through- 
out the entire succession of alternations of level from that 
movement all perturbations of the surface down to the final 
partial re-elevation appear to have taken place unequally, the 
*Thi8 occurs in the form of solid exfohations of prismatic or cleavage 
blocks of the sandstone with the hard and dense ferriferous product up 
to several inches in thickness. The interior of such weathered blocks 
is hollow and partially occupied with bleached siliceous residues in the 
form of sand. In more advanced stages of alteration and decay the fer- 
riferous product takes the form of magnetic sands. Washed into the 
streams, these finally collect on the shores of Grey's harbor and adja 
cent ocean beaches where they have long been known as considerable 
accumulations, concentrated by the tides. The analysis of solid crusts 
from pits near Elma, is as follows: Iron. 47.70; silica, (free) 6.39; alu- 
mina, 23.84; moisture, 4,22 (C. E. Bogardus). 
