What was passing in her mind at this supreme moment? We may well believe that she saw clearly the past through the mists which obscured the future. Always she had been a log at the mercy of a drunken father. Her mother had died in giving birth to her, but she knew vaguely that this mother was a Church member. She did not know--and, knowing, could never have understood--that from her she had inherited a conscience--or shall we call it an ineradicable instinct?--which constrained her to turn aside, shuddering, from certain temptations, to obey, without reasoning, certain ethical laws, solemnly expounded to her by a Calvinistic grandmother. But Nature had been too much for her. Even as she had turned instinctively and with horror from the breaking of a commandment, so also she had selected the mate who possessed in excess the physical qualities so conspicuously lacking in her. She had fallen a victim, and a reluctant victim, to the law of compensation. When Tom Barker held up his finger and whistled, she crawled to him. The log, slightly rolling, as if intoxicated, neared the brink of the falls. And then it stopped again, where the river was narrowest and the current strongest. No log had stopped in this place before; Mamie saw that it was caught by a small rock, and held fast by the other logs behind it. "It won't go over," she murmured. Within a minute a terrific jam impended. Across the river Tom was swearing horribly; and between husband and wife rose a filmy cloud of spray upon which were imprinted the mysterious colours of the rainbow, which, long ago, Mamie had been taught to regard as the most wonderful symbol in the world--God's promise that in the end good should triumph over evil. Afraid to move, fascinated, she stood still, staring at the rainbow. Presently Tom disappeared. When he returned Mamie could see him very plainly. He had a stick of dynamite and a fuse. Mamie saw him glance at his watch and measure the fuse. Then, leaping from log to log, he approached the one in midstream which lay passive, blocking the advance of all the others. With splendid skill and daring he adjusted the dynamite upon the small rock which held the log, and lit the fuse. He returned as he had come, and Mamie could hear the cheers of the men upon the opposite bank. "It'll hev to go now," she reflected. At this moment Dennis, the dog, must have realised that his master had left something behind on the rock. Mamie saw him spring from log to log, and then, holding the dynamite between his teeth, with the spluttering fuse still attached, follow his master. "Tom!" she screamed. "Look out!" Tom turned and saw! And the others--Dennis Brown, Mamie, the river- drivers--saw also and trembled. Tom began to curse the dog, adjuring him to go back, to drop it, _drop IT_, DROP IT!