Never had Broken Tooth been placed between two deadlier or more ferocious enemies than the two that now assailed him. On shore Kazan was his master because of his swiftness, keener scent, and fighting trickery. In the water the otter was a still greater menace. He was swifter than the fish that he caught for food. His teeth were like steel needles. He was so sleek and slippery that it would have been impossible for them to hold him with their chisel-like teeth could they have caught him. The otter, like the beaver, possessed no hunger for blood. Yet in all the Northland he was the greatest destroyer of their kind--an even greater destroyer than man. He came and passed like a plague, and it was in the coldest days of winter that greatest destruction came with him. In those days he did not assault the beavers in their snug houses. He did what man could do only with dynamite--made an embrasure through their dam. Swiftly the water would fall, the surface ice would crash down, and the beaver houses would be left out of water. Then followed death for the beavers--starvation and cold. With the protecting water gone from about their houses, the drained pond a chaotic mass of broken ice, and the temperature forty or fifty degrees below zero, they would die within a few hours. For the beaver, with his thick coat of fur, can stand less cold than man. Through all the long winter the water about his home is as necessary to him as fire to a child. But it was summer now and Broken Tooth and his colony had no very great fear of the otter. It would cost them some labor to repair the damage he did, but there was plenty of food and it was warm. For two days the otter frisked about the dam and the deep water of the pond. Kazan took him for a beaver, and tried vainly to stalk him. The otter regarded Kazan suspiciously and kept well out of his way. Neither knew that the other was an ally. Meanwhile the beavers continued their work with greater caution. The water in the pond had now risen to a point where the engineers had begun the construction of three lodges. On the third day the destructive instinct of the otter began its work. He began to examine the dam, close down to the foundation. It was not long before he found a weak spot to begin work on, and with his sharp teeth and small bullet-like head he commenced his drilling operations. Inch by inch he worked his way through the dam, burrowing and gnawing over and under the timbers, and always through the cement. The round hole he made was fully seven inches in diameter. In six hours he had cut it through the five-foot base of the dam.