Page:Alaska days with John Muir.djvu/75

Rh rain and snow. He had not the modern surveyor's instruments, boats or other helps. And, besides, this region was changing more rapidly than, perhaps, any other part of the globe. Volcanic islands were being born out of the depths of the ocean; landslides were filling up channels between the islands; tides and rivers were opening new passages and closing old ones; and, more than all, those mightiest tools of the great Engineer, the glaciers, were furrowing valleys, dumping millions of tons of silt into the sea, forming islands, promontories and isthmuses, and by their recession letting the sea into deep and long fiords, forming great bays, inlets and passages, many of which did not exist in Vancouver's time. In certain localities the living glacier stream was breaking off bergs so fast that the resultant bays were lengthening a mile or more