Nature: Mans Earliest Clock
THE story of the watch that you hold in your hand to-day began countless centuries ago, and is as long as the history of the human race. When our earliest ancestors, living in caves, noted the regular succession of day and night, and saw how the shadows changed regularly in length and direction as day grew on toward night, then was the first, faint, feeble germ of the beginning of time-reckoning and time-measurement. The world was very, very young, so far as man was concerned, when there occurred some such scene as this:
It is early morning. The soft, red sandstone cliffs are bathed in the golden glow of dawn. As the great sun climbs higher in the eastern sky, the sharply outlined shadow of the opposite cliff descends slowly along the western wall of the narrow canyon. A shaggy head appears from an opening, half-way up the cliff, and is followed by the grotesque, stooping figure of a long-armed man, hairy and nearly naked, save for a girdle of skins. He grasps a short, thick stick, to one end of which a sharpened stone has been bound by many crossing thongs, and, without a word, he makes his way down among the bushes and stones toward the bed of the creek.
Another head appears at the same opening in the cliff-that of a brown-skinned woman with high cheek-bones, a flat nose, and tangled hair. She shouts after the retreating form of the man, and he stops, and turns abruptly. Then he points to the edge of the shadow far above his, and, with a sweeping gesture, indicates a large angular rock lying in the bed of the stream near by. Apparently understanding the woman nods and the man soon disappears into the brush.
The forenoon wears along, and the line of shadow creeps down the face of the canyon wall until it falls at last across the angular rock against which the dashing waters of the stream are breaking. The woman who has been moving about near the cave opening begins to look expectant and to cast quick glances up and down the canyon. Presently the rattle of stones caught her ear and she sees the long-armed man picking his way down a steep trail. He still carries his stone-headed club in one hand, while from the other there swings by the tail the body of a small, furry animal. Her eyes flash hungrily, and she shows her strong, white teeth in a grin of anticipation.
Perhaps it has not been hard to follow the meaning of this little drama of primitive human need. Our own needs are not so very different, even in this day, although our manners and methods have somewhat changed since the time of the caveman. Like ourselves, this savage pair awoke with sharpened appetite, but, unlike ourselves, they had neither pantry nor grocery store to supply them. Their meal-to-be, which was looking for its own breakfast among the rocks and trees, must be found and killed for the superior needs of mankind, and the hungry woman had called after her mate in order to learn when he expected to return.
No timepieces were available, but that great timepiece of nature, the sun, by which we still test the accuracy of our clocks and watches, and a shadow falling upon a certain stone, served the need of this primitive cave-dweller in making and keeping an appointment.
The sun has been, from the earliest days, the master of Time. He answered the caveman's purpose very well. The rising of the sun meant that it was time to get up; his setting brought darkness and the time to go to sleep. It was a simple system, but, then, society in those days was simple--and strenuous.
For example, it was necessary to procure a new supply of food nearly every day, as prehistoric man knew little of preserving methods. Procuring food was not so easy as one might think. It meant long and crafty hunts for game, and journeys in search of fruits and nuts. All this required daylight. By night-time the caveman was ready enough to crawl into his rock-home and sleep until the sun and his clamoring appetite called him forth once more. In fact, his life was very like that of the beasts and the birds.
But, of course, he was a man, after all. This means that a human brain was slowly developing behind his sloping forehead, and he could not stop progressing.
After a while--a long while, probably--we find him and his fellows gathered together into tribes and fighting over the possession of hunting-grounds or what not, after the amiable human fashion. Thus, society was born, and with it, organization. Tribal warfare implied working together; working together required planning ahead and making appointments; making appointments demanded the making of them by something--by some kind of a timepiece that could indicate more than a single day, since the daily position of light and shadows was now no longer sufficient. Man looked to the sky again and found such a timepiece.
Next to the sun, the moon is the most conspicuous of the heavenly objects. Its name means "the Measurer of Time." As our first ancestors perceived, the moon seemed to have the strange property of changing shape; sometimes it was a brilliant disk; sometimes a crescent; sometimes it failed to appear at all. These changes occurred over and over again--always in the same order, and the same number of days apart. What, then, could be more convenient than for the men inhabiting neighboring valleys to agree to meet at a certain spot, with arms and with several days' provisions, at the time of the next full moon?--moonlight being also propitious for a night attack.
For this and other reasons, the moon was added to the sun as a human timepiece, and man began to show his mental resources--he was able to plan ahead. Note, however, that he was not concerned with measuring the passage of time, but merely with fixing upon a future date; it was not a question of how long but of when.
This presumptuous, two-legged fighting animal, from whom we are descended, and many of whose instincts we still retain, began to enlarge his warfare, and thereby to improve his organization. For the sake of his own safety, he learned to combine with his fellows, finding strength in numbers, like the wolves in the pack; or, like ants and bees, finding in the combined efforts of many a means of gaining for each individual more food and better shelter than he could win for himself alone.
For example, it was possible that a neighboring tribe, instead of waiting to be attacked, was planning an attack upon its own account. It would not do to be surprised at night. Sentries must be established to keep watch while others slept, and to waken their comrades in case of need. Our very word "watch" is derived from the old Anglo-Saxon word "waeccan," meaning "wake." And yet people who tried to watch for long at a stretch would be apt to doze. They must be relieved at regular times; it was a matter of necessity, but how could one measure time at night?
Where man has been confronted with a pressing problem he has generally found its solution. Probably in this case the stars gave him a clue. If the sky were clear, their positions would help to divide the night into "watches" of convenient length.
Thus did primitive man begin to study the skies. No longer a mere animal, he was beginning, quite unconsciously, to give indications of becoming a student.