It cannot well be compared to a mountain or a machine or any physical thing, for they exist continuously of the same materials. But a storm constantly draws into itself new air and casts out the old.

In this a storm is like a wave or whirlpool which exists in the water but never of the same water. But a storm is vastly more complicated than any wave or whirlpool.

There is a closer analogy—with a living organism, even with a human being. As a man is conceived in the fierce onset of opposing natures, so also a storm begins in the clash of the dry cold air from the north and the mild moist air of the south. Like a person, a storm is a focus of activities, continuing and varying through a longer or shorter period of time, having a birth, youth, maturity, old age, and death. It moves; in a sense, it reproduces its kind, and even takes in food, exhausts it of energy, and casts out the waste. The storm, to be sure, develops only in a manner determined by its antecedents and environment—but many philosophers think little also of man’s apparent free will. As for sensation and consciousness of which we talk much and know little—a storm seems to sheer off from a high-pressure area much as the human hand shrinks from the touched nettle.

But a community or a nation yields a still better analogy. Rome or England may endure through centuries although Romans and Englishmen die and are born hourly. The new storms sprung of the old are more like colonies than children; as with Rome and Constantinople there may be doubt as to which maintains the continuity of empire. The life-cycle of a storm is like that of a nation which from apparent decadence is sometimes renewed into full vigor. Finally a storm, like a nation, has an indefinable abstract existence. Men speak of England when they mean neither its land nor its government nor its people, but merely some symbolic centuries-old ideal. And more, when men think thus, tears come to their eyes, and they march with high hearts to battle. So also in every storm exists a something which meteorologists cumbersomely name “a center of low pressure.” This is neither air, nor cloud, nor wind, nor rain—yet, as with a nation, this mere abstraction represents the continuing reality of a storm.

2

From the Arctic islands and the ice-floes of Beaufort Sea, from the tundras and pine-barrens and frozen lakes, the polar air swept southward across the plains. Its overwhelming front rushed onward at fifty miles an hour.