About the 20th March the hunters sighted the first swans migrating from the south, and uttering shrill cries as they flew. A few snow buntings and winter hawks were also seen. But the ground was still covered with thick layers of frozen snow, and the sun was powerless to melt the hard surface of the lake and sea. The breaking up of the frost did not commence until early in April. The ice burst with a noise like the discharge of artillery. Sudden changes took place in the appearance of the icebergs broken by collisions, undermined by the action of the water once more set free, huge masses rolled over with an awful crash, in consequence of the displacement of their centre of gravity, causing fractures and fissures in the ice-fields which greatly accelerated their breaking up. At this time the mean temperature was 32° above zero, so that the upper layer of ice on the beach rapidly dissolved, whilst the chain of icebergs, drifted along by the currents of the Polar Sea, gradually drew back and became lost in the fogs on the horizon. On the 15th April the sea was open, and a vessel from the Pacific Ocean coming through Behring Strait, could certainly have skirted along the American coast, and have anchored off Cape Bathurst. Whilst the ice was disappearing from the ocean, Lake Barnett was also laying aside its slippery armour, much to the delight of the thousands of ducks and other water-fowl which began to teem upon its banks. As Hobson had foreseen, however, the level of the lake was affected by the slope of the soil. That part of the beach which stretched away from the enceinte of the fort, and was bounded on the east by wooded hills, had increased considerably in extent; and Hobson estimated that the waters of the lake had receded five hundred paces on the eastern bank. As a natural consequence, the water on the western side had risen, and if not held back by some natural barrier, would inundate the country. On the whole, it was fortunate that the slope was from east to west; for had it been from west to east, the factory must have been submerged. The little river dried up as soon as the thaw set free its waters. It might almost be said to have run back to its source, so abrupt was the slope of its bed from north to south. “We have now to erase a river from the map of the Arctic regions,” observed Hobson to his Sergeant. “It would have been embarrassing if we had been dependent on the truant for drinkable water. Fortunately we have still Lake Barnett, and I don’t suppose our thirsty men will drain it quite dry.” “Yes, we’ve got the lake,” replied the Sergeant; “but do you think its waters have remained sweet?” Hobson started and looked at his subordinate with knitted brows. It had not occurred to him that a fissure in the ground might have established a communication between the lake and the sea! Should it be so, ruin must ensue, and the factory would inevitably have to be abandoned after all.