The annual migration is a different affair. This has been noted for some hundred and fifty years or more, and probably has gone on for centuries. This peculiar migration might be called a migratory outing. In it all members of the colony appear to have taken part, leaving home in June, scattering as the season advanced. Rambles were made up and down stream, other beaver settlements visited, brief stays made at lakes, adventures had up shallow brooks, and daring journeys made on portages. The country was explored. The dangers and restrictions imposed during the last twenty-five years appear in some localities to have checked this movement, and in others to have stopped it completely. But in most colonies it still goes on, though probably not usually enjoyed by mothers and children except to a limited extent. By the first of September all have returned to the home, or joined another colony or assembled at the place where a new colony is to be founded. This annual vacation probably sustained the health of the colonists; they got away from the parasites and the bad air of their houses. The outing was taken for the sheer joy of it. Incidentally, it brought beaver into new territory and acquainted them with desirable colony-sites and the route thereto,--useful information in case the colonists were compelled suddenly to abandon the old home. It is natural for the beaver to be silent. In silence he becomes intimate with the elements, and, while listening, hears and understands all moods and movements that concern him. He is a master in translating sound. It wakens or warns, threatens or gladdens, and woos him back to slumberland. On the wild frontier in his fortress island home in safety he sits and sleeps in darkness. He cannot see outside, but the ever-changing conditions of the surrounding outer world are revealed to him by continuous and varying sounds that penetrate the thick windowless walls of his house. He hears the cries of the coyote and the cougar, the call of moose, the wild and fleeting laugh of the kingfisher, the elemental melody of the ouzel, and many an echo faintly from afar. He hears the soft vibrations from the muffled feet of enemies; and, above his head, the raking threat of claws upon the top of his house. Endlessly the water slides and gently pours over the dam, and softly ebbs around the pond's primeval shores. The earthquake thunder warns of storm, the floods roar; then through day and night the cleared and calmed stream goes by. The wind booms among the baffling pines, and the broken and leafless tree falls with a crash! There is silence! Along the stream's open way through the woods numberless breezes whisper and pause by the primitive house in the water. The Beaver's Engineering