So you see the beaver had planned his work well and the frost and the wind had helped him. He had harnessed the stream to do his work, and made its water protect him from his enemies. Just as men built their castles in days of old, the beaver had made his dam, so that a moat should surround his house, where the drawbridge should always be up, and the only way of entrance or exit should be by water.
You may wonder how after the roof of their house had been closed up, and no door left, the beavers went to and from their dwelling, but do you not remember the three holes that had been dug several weeks before. These were now their three submerged channels to the outer world, through which only a good swimmer could pass. This was the way they went. A plunge down the hole at the centre of the lodge, and a dark form would shoot out at the bank of the river. Perhaps a beaver's head, dripping with water would be poked up, only a few feet from the mud house, or maybe they would go the entire width of the pond before coming to the surface, for they are great swimmers, and can stay down for several minutes without coming to the surface to breathe.
Besides having three doors through which to escape to their water world, the beavers took other precautions against being entrapped in their snug house, or caught in the pond without a place of refuge to flee to.
They searched the bank for places where it was steep or shelving, overhanging the water. At such points they dug burrows back into the bank, gradually running them upward, but stopping a foot or two short of the surface. Here they would scoop out a snug burrow or nest to which they could retreat when living in the house became dangerous. They made three or four such burrows, the lower end of each being under water, and the nest end high and dry, but still underground. By this time they felt that their pond was fairly well fortified, and they set to work, laying in their winter store of food, for they knew that the pond would soon freeze over thus making them prisoners under the ice for the entire winter, so they must make their plans accordingly.
They went to the upper end of the pond and began felling birch, poplar and maple saplings, three or four inches in diameter. These small trees they limbed out, and cut up into pieces about three feet in length, just as a wood-chopper would cut cord wood.
When a tree had been cut up into these convenient pieces, one of the beavers would load it upon the shoulders of the other, who would cling to the stick with his teeth, and they would begin dragging it to the water. The beaver usually went obliquely, dragging the stick after him, with one end trailing. When it had been rolled into the water, it was left to the current which they knew would float it down to the dam. If the channel became blocked and logs lodged along the shore, they pushed them off like the good log-men they were.
It took two or three weeks to cut the winter's supply of wood, which was not for fuel but food. All the logs had been floated down to the dam and secured under water near the lodge, when the great freeze came. It was quite difficult to make the sticks stay under water, but this they managed to do in several ways. Some of them they thrust into the mud, while others were secured under roots, and a large pile was made safe at the dam by thrusting one stick under another and allowing the top sticks to keep the under ones down.
One clear, crisp night, about the first of December, the North Wind awoke and came galloping over the frozen fields, bringing with him legions of frost folks. The fingers of these myriad little people were like icicles, and everything that they touched was congealed. They found the beavers' pond, and danced a merry dance over the sparkling water, and every time that they stooped to touch the clear water, crystals of ice formed and spread in every direction.
It had been a very pleasant autumn, but the North Wind was angry to-night, and he howled like a demon, and smote lake and river with his icy mittens, so that when the sun rose next morning, lakes and streams were cased in a glittering armor of ice and the beavers were prisoners for the winter.