2 It! The AiiKi'Kil n (tfoliKjtsf. (Htober, 18M 
tlir sauu' takt'ii liy l)r. Wv'uX and Mr. ^I<)l•s^'. As a result of his 
nieasurc'incnts of tlie rate of motion of Miiir glacier 
near its front. l*rof. AVright announces an average forward move- 
ment of the ice into the inlet of forty feet a da}', with a maxi- 
mum of seventy feet.* His method was l»y sigliting on vai'ious 
pinnacles of the deeply crevassed portion of the ice, from day to 
day. rndcr Dr. Reids skillful guidance our party made several 
ertorts to completelv cross the ice front and plant Hags to serve 
as accurate points on which to sight. The attempt to entirely 
cross was unsuccessful, proving a task of the most extreme diffi- 
culty, if not impossililo. By working out from each side to\j'ard 
the centre, however, the last flag on one side was planted so near 
to the last flag on the other, that the space between the two was 
less than the average interval left between the others. The 
most rapid motion found V)v Dr. Reid by triangulation upon these 
flags, was seven feet a day. Undoubtedly the ice was in more 
rapid motion at the time of Prof. "Wrights visit. Its greater 
thickness and the fact that it was further advanced into the com- 
paratively narrow valley in which Muir inlet lies would necessi- 
tate this. But the increased rapidity must have l)een compara- 
tively small in amount. 
FresJmess and extent of stria. — The sides of the mountains 
])ordering Muir inlet are polished and striated with the freshest 
possible marks up to hights of 2,00U feet. The same is true of 
the sides and tops of the two low islands which project above the 
surface of Muir inlet. Naturally the striations decrease gradually 
in number and strength as the altitude increases owing to the- 
rapid disintegration of the rocks. Above 2,000 feet strife are 
occasionally found up to hights as great as 3,500 feet. Only 
occasional peaks have hights over 8,000 feet, hence when 
glaciation was at its hight the whole region must haA'c been 
covered with an icy mantle with only here and there a small steep 
crag projecting above the general level. In the upper portion of 
Glacier V)ay the same fi^eshness of the striae is observable on the 
mountain sides and the islands in the bav. Going down the l)ay 
the same decrease in number and freshness is observed that is 
found (jn increase of altitude. Yet the differences are not as 
marked as would Uv the case had the retreat of tlic ice been a slow 
♦Ice Age in North America, pp. 48 — 51. 
