Note 3 — Chapter IV · TRANSACTIONS AMONGST THE NATIVES OF NORTH AMERICA; DISCOVERIES ALONG THAT COAST AND THE EASTERN EXTREMITY OF ASIA, NORTHWARD TO ICY CAPE; AND RETURN SOUTHWARD TO THE SANDWICH ISLANDS. (continued 3)

Footnote 3:

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These observations of Captain Cook, in addition to some remarks which were formerly given on the subject, seem conclusive against the supposition of such large masses of ice being the product of rivers, as has not unfrequently been maintained. They may, however, have proceeded from land in another way, being occasioned by the consolidation of snow into such masses as were of sufficient weight to separate from the declivities where they had been formed. This undoubtedly may sometimes happen; but the explanation of their origin formerly offered, seems much more entitled to consideration, as a generally operating cause. The last remark which Captain Cook makes, appears to have been levelled at some would-be-wise heads, who had hazarded reflections about the possibility of some time or other finding an open sea in high latitudes. But, however illiberally stated, it is in all probability just, though for a reason unknown to Cook. The chemical reader will perceive we allude to the circumstance of the absorption of heat that takes places during the liquefaction of ice, in consequence of which the temperature of the surrounding atmosphere is reduced so much, as to prevent any more of the ice being dissolved. A contrary operation, as is now well known, takes place during the congelation of water, and heat is evolved. Thus then the cold of winter is moderated. And so, on the whole, the temperature is kept more uniform, than, without such adjustment, would be the case.—E.