On one occasion Franklin and Beechey, when out in a boat together, witnessed the launch of an iceberg. They had approached the end of a glacier and were trying to search into the recess of a deep cavern at its foot when they heard a report as if of a cannon, and, turning to the quarter whence it proceeded, perceived an immense piece of the front of the cliff of ice gliding down from a height of two hundred feet at least into the sea, and dispersing the water in every direction, accompanied by a loud grinding noise, and followed by a quantity of water, which, lodged in the fissures, made its escape in numberless small cataracts over the front of the glacier. They kept the boat's head in the direction of the sea and thus escaped disaster, for the disturbance occasioned by the plunge of this enormous fragment caused a succession of rollers, which swept over the surface of the bay, making its shores resound as it travelled along it, and at a distance of four miles was so considerable that it became necessary to right the _Dorothea_, which was then careening, by instantly releasing the tackles which confined her. The piece that had been disengaged wholly disappeared under water, and nothing was seen but a violent boiling of the sea and a shooting up of clouds of spray like that which occurs at the foot of a great cataract. After a short time it reappeared, raising its head full a hundred feet above the surface, with water pouring down from all parts of it; and then, labouring as if doubtful which way it should fall, it rolled over, and, after rocking about for some minutes, became settled. It was nearly a quarter of a mile round and floated sixty feet out of the water, and making a fair allowance for its inequalities, was computed to weigh 421,600 tons. [Illustration: TRACK OF H.M.S. "DOROTHEA" AND "TRENT"]