We did not then know it, but, at the very moment Guert was thus urging his blacks to supernatural efforts--actually running them as if on a race-course--there was a long reach of the Hudson, opposite to, for a short distance below, and for a considerable distance above the town, which was quite clear of stationary ice. Vast cakes continued to come down, it is true, passing on to increase the dam that had formed below, near and on the Overslaugh, where it was buttressed by the islands, and rested on the bottom; but the whole of that firm field, on which we had first driven forth that morning, had disappeared! This we did not know at the time, or it might have changed the direction of Guert's movements; but I learned it afterwards, when placed in a situation to inquire into the causes of what had occurred. Herman Mordaunt's bells, and the rumbling sound of his runners, were heard close behind us, as our own sleigh flew along the river at a rate that I firmly believe could not have been much less than that of twenty miles in the hour. As we were whirled northward, the reports made by the rending of the ice increased in frequency and force. They really became appalling! Still, the girls continued silent, maintaining their self-command in a most admirable manner; though I doubt not that they felt, in the fullest extent, the true character of the awful circumstances in which we were placed. Such was the state of things, as Guert's blacks began sensibly to relax in their speed, for want of wind. They still galloped on, but it was no longer with the swiftness of the wind; and their master became sensible of the folly of hoping to reach the town ere the catastrophe should arrive. He reined in his panting horses, therefore, and was just falling into a trot, as a violent report was heard directly in our front. At the next instant the ice rose, positively, beneath our horses' hoofs, to the height of several feet, taking the form of the roof of a house. It was too late to retreat, and Guert shouting out “Jack”--“Moses,” applied the whip, and the spirited animals actually went over the mound, leaping a crack three feet in width, and reaching the level ice beyond. All this was done, as it might be, in the twinkling of an eye. While the sleigh flew over this ridge, it was with difficulty I held the girls in their seats; though Guert stood nobly erect, like the pine that is too firmly rooted to yield to the tempest. No sooner was the danger passed, however, than he pulled up, and came to a dead halt. We heard the bells of Herman Mordaunt's sleigh, on the other side of the barrier, but could see nothing. The broken cakes, pressed upon by millions of tons weight above, had risen fully ten feet, into an inclination that was nearly perpendicular; rendering crossing it next to impossible, even to one a-foot. Then came Herman Mordaunt's voice, filled with paternal agony, and human grief, to increase the awe of that dreadful moment!