lí
i 1[
peaks in the snow-clad range is under 7 0 0 0 feet, it is evident
that the height of the snow-line cannot at most much
exceed 6000 feet.
As this is a point of interest, I shall mention a few other
circumstances, by which I think we may come to a nearly
definite conclusion. On February 2d (1835) I obtained
the last view of the Cordillera; on that day the lower line
of the snow descended some way (so as to form a considerable
angle with the summit, when viewed from a
distance of 61 miles) on the mountain south of Osorno (lat.
41° 20'), which stands by itself, and has a height of 5607
feet. Since arriving in England I have received a letter
from Mr. Douglas in Chiloe, who, describing some volcanic
phenomena, accidentally mentions the snow-line. He says,
on February 20th (same year), on the volcano of Minchinmadiva
(lat. 42° 48'), which has an elevation of 7046 feet,
lava was ejected from a crater “ just above the verge of
the snow.” Again, on February 27th, he alludes to the
summit of the Corcovado (7510 feet) being covered with
snow, as was Ahítales* (6725 feet) in lat. 43° 30 . Again
Mr. Douglas, speaking of the Corcovado, says, “ On the
16th of March the snow appeared to cover one-fifth of its
{pisibld} perpendicular height.” By this date the snow-line
must have attained its greate.st height (if, indeed, fresh
snow had not fallen); and, as the Corcovado rises in an
unbroken slope close to the sea, the proportion covered
by snow might be judged of, with some degree of accuracy.
The height of the Corcovado (7510 feet) was obtained hy
three angular measurements, made by the officers on the
survey, and the mean nearly agreed with the three separate
results. Reflecting on all these circumstances, we may
conclude with perfect safety, that the limit of perpetual
snow, between the latitudes 41° and 43°, cannot much, if
at all, exceed 6000 feet.
Proceeding northward along the Cordillera we find a very
» O n J a n u a ry lo tli, Y n ta le s , s e e n from th e N o r th e r n C h o n o s Isla n d s ,
was e n tir e ly co v e red b y snow.
different condition of things. In the pass of the Portillo (to
the southward of .33°) Dr. Gillies determined barometrically
the height of the double range ; and he found the two ridges
to be respectively 13,210 and 14,365 feet. On March 21st
and 22d (1835), shortly before fresh snow fell, I crossed
these mountain.s,* and although there were large masses of
snow, there were much greater spaces at some height on each
side uncovered. Dr. GiUies'f says, “ the summit (of the
volcano of Peuquenes) is generally! covered with snow, and
its elevation cannot be less than 15,000 above the level of
the sea.” From these statements, compared with my observations,
the snow-line when I crossed certainly was considerably
above 14,365,—we may assume 15,000 as about
the limit. From the results obtained by Humboldt, Pentland,
Gillies, and King, we are enabled to draw up the
following table of the extraordinary range of the snow-line
on the Cordillera of South America:
Latitude.
E q u a to r ia l reg io n :
M e an re s u lt.
Bo liv ia ,
L a t. 160-180 S.
C e n tra l C h ile ,
L a t . 3 3 ° S.
C h ilo e ,
L a t. 4 1 ° -4 3 ° S.
T ie r r a d e l F u e g o ,
5 4 ° S.
Height in feet
of Snow-line. Observer.
15,748 H um b o ld t.
17,000 P e n tla n d .^
f 14,500
d. to
G illie s.
1 15,000
6,000 Officers o f th e Beagle.
r 3 ,5 0 0
i to
t 4 ,0 0 0
K in g . II
* I cro ssed th e U s p a lla ta P a s s o n A p r il S th . T h e h e ig h t, as g iv en b y
Mr. P e n t la n d (G e o g r a p h ic a l J o u rn a l ) , is 12,454. I n th e r av in e s th e r e
w e re some in co n s id e ra b le p a tc h e s o f sn ow, b u t th e g e n e ra l s u rfa c e was
q u i te b a re .
f T h e E d in b u rg h J o u rn a l o f N a tu r a l a n d G e o g r a p h ic a l S c ien c e ,
A u g u s t, 1830, p. 3 16.
f I h av e re a so n to su sp e c t th a t th e sn ow -lin e in C h ile is s u b je c t to ex -