Swollen by recent rains, the river is two feet higher than usual. There is a sheet of ice on either shore, but the water swiftly flows down the narrow channel in the middle with a sound halfway between a gurgle and a roar, mingled anon with the sound of grinding cakes of ice. Suddenly away up at the bend of the river there is a sharp crack, like the discharge of a volley of musketry. Swiftly it comes down the ice, passes your feet with a distinct tremor, and your eyes follow the sound down the river until the two walls of the canon meet in the perspective. In a small way you know how it would feel to hear the rumble of an approaching seismic shock. Only there was no terror in this. It was the laughter of the sunbeam fairies as they loosened the architecture of "the elfin builders of the frost." The recent rains have vivified the mosses clinging to the gray rocks which jut out, halfway up the slope. Very tender and beautiful is their vivid shade of green. Winter and summer, the mosses are always with us. When the last late aster has faded, the last blue blossom of the gentian changed to brown, the green mosses still remain. And the more they are studied, the more fascinating they become. Take some home and examine them with a hand lens, then with a microscope. You will be charmed with the exquisite finish of their most minute parts. Nature glories in the artistic excellence of infinitesimal workmanship. The most beautiful part of her handiwork is that which is seen through a microscope. There is beauty, beauty everywhere; the crystals of the snow, the cell structure of the leaf, the scales of the butterfly's wing, the pedicels, capsules and cilia of these mosses. No wonder that many distinguished men have been led to give their whole lives to the study of mosses and have felt well repaid. * * * * * Here are Nature's only two elementary forms of growth, the cell and the crystal, wrestling for the mastery over each other in a life and death struggle. The moss is built up of cell, the rock of crystal forms. Below this Devonian limestone, its crystals sparkling in the sunshine, with its coral fossils, its fragments of crinoids, and its broken shells of brachiopods, down through the Devonian, the Silurian, the Ordovician, and the Cambrian rocks, down to the original crust formed when first the earth began to cool, if any there be remaining; all these miles of rocks are inorganic, built up of crystals. But here on the surface, the tender green mosses and the bright lichens have begun the struggle of the cellular system for supremacy. These humble little rock-breakers will not rest until they have pulverized the rocks into soil sufficient to sustain higher forms of vegetable life.