8 PHILOSOPHICAL SOCIETY OF WASHINGTON. 
Mr. Wiis remarked that in 1883 he had had opportunity to 
study the Cascade Mountains north of the regiom described by Mr. 
Diller. The Sierra structure is apparently not found in the north- 
ern part of Washington Territory, and the eastern face of the 
Cascade range is probably not characterized like the Sierra by a 
great fault. 
Mr. Drier concurred in the statement that the Cascade range 
is built essentially of igneous rocks, and is not characterized by 
great faults, at least along its eastern base. 
The topography of the Sierra has entirely changed since the 
deposition of the auriferous gravels, and some of the fault move- 
ments are so recent that the stream terraces to which they have 
given rise are still preserved. 
Mr. G. K. GILBERT made a communication on 
RECENT CHANGES OF LEVEL IN THE BASIN OF LAKE ONTARIO. 
[The substance of this communication was presented to the 
American Association for the Advancement of Science at Ann 
Arbor, and appears in abstract in Science, Vol. VI, p. 222.] 
Remarks were made by Mr. E. Farqunar. 
280TH MEETING. JANUARY 30, 1886 
The President in the Chair. 
Fifty-five members and guests present. 
The Chair announced the appointment of the Committee on 
Communications. 
Mr. Greorce E. Curtis made a communication on 
LIEUTENANT LOCKWOOD’S EXPEDITION TO FARTHEST NORTH. 
[Abstract. ] 
The paper opened with a reference to the statement in the Ency- 
clopedia Britannica (article, Polar Regions, p. 326,) that “all this 
region [the northern coast of Greenland and the interior of Grinnell 
