Geology of the Piujet Sound Basil}. — Kimball. 238 
from the point where it makes its first appearance in the blutf . 
Thanks to Mr. R, H. Thompson, city engineer of Seattle, the 
ledge which had been graded olf was laid bare for my exami- 
nation. As at Point Glover, it is there seen to possess a di- 
visional structure. A narrow zone of sound rock thus visible 
is characterized by a porcellanic magma mottled with spheru- 
lites. These differentiate in weathering. Hence the pebbly 
aspect as seen in the bluff. Certain decomposed divisional 
parts under cover are extremely cellular and quite unlike an}^- 
thing seen in the bluff*, but of similar type to certain parts of 
the Point Glover belt. While the eruptive character of this 
ledge is pronounced, the pebbly, and in part breceiated, ma- 
terial first described is with difficulty identified, macroscopic- 
ally at least, as of similar character. By gradation, however, 
it may be traced into sound rock in a quarry at Cardmore, 
through a number of intervening outcrops in the bluff, which 
in that direction is broken into hills. Above Cardmore the 
same rock is preserved in jirominences on both sides of the 
Duwamish. The identity of this belt with that of Point 
Glover has already been indicated on grounds of uniform re- 
lations, strike, lithological character, and divisional constitu- 
tion. This occurrence has been described in some detail 
because it differs extremely from all other eruptive products 
which have come to my notice in the elevated border of 
the sound. These are generally of the types of diabase and 
basalt. 
According to Mr. Thompson, Wing point on Eagle harbor 
(Bainbridge island) is of solid formation. Basaltic survivals 
are reported by Mr. Whitworth at the head of Sinclair inlet, 
and again about midway of the north township line to the 
west (R 1 E., T. 23), and also directly to the north on the 
next township line. Hood's canal at the base of the Olympics 
is well known to be bordered on the west by a long stretch of 
basaltic rock between Lilliwaup river and Quilcene bay. Sim- 
ilar rock is said to be exposed at Dewatto bay on the east 
shore of the same inlet, and again at Hood's head. 
At Volcano point, Double bluff, as I am informed by Mr. 
Whitworth, a series of soft sandstones is exposed near tide. Im- 
bedded in a seam of lignite within this series were found sev- 
eral years ago, according to this observer, vertebrate remains. 
