Fig. 19. Snow crystals enlarged.
But another change is sure to come. Some February day the wind will veer suddenly to the south and breathe warm thawing breaths over the white frozen world. Then will the forests appear in robes of vivid blue-purple against the shining hills; and in the mornings the soft blue of the horizon will shade upward into rose-color and still upward into yellow and beryl green; these hues are never seen on the forest or in the sky except when the snow covers the earth to the horizon line. The eye that loves color could ill afford to lose from the world the purples and blues which bring contrast into the winter landscape.
The snow storm to our limited understanding, begins with a miracle—the miracle of crystallization. Why should water freezing freely in the air be a part of geometry, the six rays of the snow crystal growing at an angle one to another, of sixty degrees? Or as if to prove geometry divine beyond cavil, sometimes the rays include angles of twice sixty degrees. Then why should the decorations of the rays assume thousands of intricate, beautiful forms, each ray of a flake ornamented exactly like its five sisters? And why should the snowflake formed in the higher clouds of the upper air be tabular in shape but still, in cross section, show that it is built on the plan of six radii? Look at it as we will, the formation of a crystal is a beautiful mystery and is as unfathomable as is the mystery of life.
Fig. 20. Snow crystals enlarged.
I am indebted to the courtesy of Mr. R. G. Allen, Section Director for New York of the U. S. Weather Bureau, for suggestions in making out the following questions. The beautiful pictures of snow crystals illustrating this lesson were made from photographs taken by Mr. W. A. Bentley of Jericho, Vt. It is our desire to interest all teachers in the natural history of a snow storm, to the end that "they may love the country better and be content to live therein."
A thermometer hung in a sheltered, open place away from the warmth of the house is a necessary preliminary to the proper observation of the phenomena of a snow storm.
Dark woolen cloth is the best medium on which to catch and observe snow crystals.
