Pencroft and Ayrton, the most zealous workmen at the new vessel, pursued their labour as long as they could. They were not men to mind the wind tearing at their hair, nor the rain wetting them to the skin, and a blow from a hammer is worth just as much in bad as in fine weather. But when a severe frost succeeded this wet period, the wood, its fibres acquiring the hardness of iron, became extremely difficult to work, and about the 10th of June ship-building was obliged to be entirely discontinued. Cyrus Harding and his companions had not omitted to observe how severe was the temperature during the winters of Lincoln Island. The cold was comparable to that experienced in the States of New England, situated at almost the same distance from the equator. In the northern hemisphere, or at any rate in the part occupied by British America and the north of the United States, this phenomenon is explained by the flat conformation of the territories bordering on the pole, and on which there is no intumescence of the soil to oppose any obstacle to the north winds; here, in Lincoln Island, this explanation would not suffice. "It has even been observed," remarked Harding one day to his companions, "that in equal latitudes the islands and coast regions are less tried by the cold than inland countries. I have often heard it asserted that the winters of Lombardy, for example, are not less rigorous than those of Scotland, which results from the sea restoring during the winter the heat which it received during the summer. Islands are, therefore, in a better situation for benefiting by this restitution." "But then, Captain Harding," asked Herbert, "why does Lincoln Island appear to escape the common law?" "That is difficult to explain," answered the engineer. "However, I should be disposed to conjecture that this peculiarity results from the situation of the island in the southern hemisphere, which, as you know, my boy, is colder than the northern hemisphere." "Yes," said Herbert, "and icebergs are met with in lower latitudes in the south than in the north of the Pacific." "That is true," remarked Pencroft, "and when I have been serving on board whalers I have seen icebergs off Cape Horn." "The severe cold experienced in Lincoln Island," said Gideon Spilett, "may then perhaps be explained by the presence of floes or icebergs comparatively near to Lincoln Island."