MR. GLACIER'S CATERPILLAR TRACTOR
"The glaciers," says Reclus, "seem as motionless as the peaks that tower above them." Nevertheless, as we know, they do move. While the motion is in so many respects like that of a river that glaciers are often called "ice rivers," they have motions and, so to say, "methods" that curiously suggest the inventions of men. Take, for example, the way they climb down a steep hill; for all the world like the "tanks" in the Great War. The tanks, you remember, made nothing of shell holes, rough country, ravines, or trenches, but lumbered and crushed their way along, resistless as the Fates. And, you may also recall, the tanks moved by laying sections of themselves—the great cleats on the outside belt—which they picked up again, as they advanced. This was called the "caterpillar tractor" system of travelling.
Now watch the glacier when it comes to an incline much steeper than its ordinary slope. It breaks across in sections at right angles to its bed, and section after section drops down. Then the forward sections crowded upon by those in the rear are pushed up close, freeze together again, and on goes the glacier as good as new.
As a traveller, however, it is a little slow. It made faster time in the old days—in the Ice Age—when glaciers were so much larger, but to-day, at the rate at which ordinary glaciers travel, it may take a boulder as big as Plymouth Rock something like a hundred years to be carried from the upper fields to the heap of stones and soil which your geography calls a "terminal moraine," and where Mr. Glacier says:
"All out! Far as we go."
HIDE AND SEEK IN THE LIBRARY
How would you like to go to school to the pretty Misses Soldanella? They can teach you a lot about botany. If you learn what an unusual thing they do with their leaves, for instance, that will lead you to follow up leaves in general. Leaves are wonderful things. Indeed, it isn't often you find the leaf of a book that will tell you half as much as the leaf of a plant, if you only know how to read it.
In Grant Allen's "Flash Lights on Nature," you will find that the Soldanella sisters store food in their leaves all winter just as we put things away in the cellar, and how this helps them get up so early in the spring; why the fact that the little sisters are not very tall makes them hurry so; and why if they didn't hurry they wouldn't get to the party at all!
What other members of the primrose family do you know?
See what you can find about our earliest flowers—hepatica, bloodroot, dog-toothed violet, jack-in-the-pulpit, Dutchman's breeches, anemones.