twenty-four days, and never did I more deeply enjoy an equal space of
time. A few days afterwards I returned to Mr. Corfield's house at
Valparaiso.
[1] Scoresby's Arctic Regions, vol. i. p. 122.
[2] I have heard it remarked in Shropshire that the water, when the
Severn is flooded from long-continued rain, is much more turbid than
when it proceeds from the snow melting in the Welsh mountains.
D'Orbigny (tom. i. p. 184), in explaining the cause of the various
colours of the rivers in South America, remarks that those with blue or
clear water have there source in the Cordillera, where the snow melts.
[3] Dr. Gillies in Journ. of Nat. and Geograph. Science, Aug., 1830.
This author gives the heights of the Passes.
[4] This structure in frozen snow was long since observed by Scoresby
in the icebergs near Spitzbergen, and, lately, with more care, by
Colonel Jackson (Journ. of Geograph. Soc., vol. v. p. 12) on the Neva.
Mr. Lyell (Principles, vol. iv. p. 360) has compared the fissures by
which the columnar structure seems to be determined, to the joints that
traverse nearly all rocks, but which are best seen in the
non-stratified masses. I may observe, that in the case of the frozen
snow, the columnar structure must be owing to a "metamorphic" action,
and not to a process during deposition.
[5] This is merely an illustration of the admirable laws, first laid
down by Mr. Lyell, on the geographical distribution of animals, as
influenced by geological changes. The whole reasoning, of course, is
founded on the assumption of the immutability of species; otherwise the
difference in the species in the two regions might be considered as
superinduced during a length of time.
CHAPTER XVI
NORTHERN CHILE AND PERU
Coast-road to Coquimbo--Great Loads carried by the
317