796 MR J. M. WORDIE ON THE NATURAL HISTORY OF PACK-ICE 
influenced by much higher summer temperatures. The Arctic ice, however, has 
never been subjected to quite the same methods of observation, and it is therefore 
better to regard this paper as the natural history, not of pack-ice in general, but of 
Weddell Sea pack-ice.* 
Historical. — -Previous to 1820 the idea seems to have prevailed that no ice. 
formed at sea. Daines Barrington and Higgins, for instance, tried to reconcile 
the reports (now known to be erroneous) of whalers, that all ice found at sea was fit 
to drink, with the fact that sea-water frozen in the laboratory was fairly salt ; they 
maintained, accordingly, that “ no considerable congelation ever takes place in the 
sea,” and that the floating ice observed in high latitudes is land-derived. In 1820, 
however, Scoresby, with the experience of many whaling voyages behind him, 
published what appears to be the earliest scientific account of the Arctic pack-ice by 
the actual observer himself. He demonstrated for the first time that ice could form on 
the sea far from land, and also showed how this ice might sometimes be fresh enough 
for drinking purposes. The mistake made in the next four decades was to imagine 
that freshness was the rule — a misconception which persisted till Walker, who 
accompanied M‘Olintock as surgeon on the Fox , published his results in 1860. 
References to ice in the Franklin Search Expeditions are of course numerous, but 
very seldom reliable ; and practically none of the writers except Rae take account 
of the physical and chemical side of the subject. Rae in later life read a short paper 
on some of his observations to the Physical Society, and made Guthrie sufficiently 
interested to make further experiments. 
When in the seventies interest became once more directed to the Arctic, a good 
deal more attention than formerly was paid to the natural history of sea-ice. Both 
Payer and his' associate Weyprecht published clear and direct accounts of what 
they saw. On the Hares Expedition, however, ideas on sea-ice became again some- 
what confused ; the term “ palseocrystic,” for instance, was introduced to include 
“ floebergs ” and heavy floes. Nares himself thought floebergs were due to direct 
freezing of sea-water ; but Moss, and later Greely, realised that they were due to 
accumulated snowfall ; and many years later Peary ' actually found them forming 
from glaciers on the north coast of Greenland. The ‘‘ palseocrystic floes,” on the 
other hand, are now regarded as simply hummocky-pack and heavy floes ; later 
travellers over the Polar Sea, however, have done little to advance knowledge in 
this respect. 
In more recent years Pettersson, Drygalski, and Hamberg have made consider- 
able additions on the physical side. Pettersson’s results especially call for 
mention, for, if accepted, they are of extreme importance ; Buchanan and others, 
however, have taken exception to his work. It now remains for someone to test in 
nature what Pettersson found in the laboratory. 
* In the forthcoming Ice Memoir of the Scott Antarctic Expedition, 1910-1913, Mr Priestley proposes to give 
an account of the Ross Sea fast-ice and pack-ice. 
