ble for the fact that now its rotation time equals its revolution period.
The Moon has been credited with many other influences upon us, malign as well as benevolent. Our words lunacy and lunatic preserve the idea once universally held that moonlight can affect the minds of men; countless wise sayings embalm the belief that the Moon affects the weather; and others, the belief that the planting of various crops, to result in fruitful harvests, must be timed to the right phase of the Moon. These are all superstitions worth as much or as little as Tom Sawyer's method of curing warts. Not one of them has a basis of fact, but they cling tenaciously to men's minds and still influence the actions of some. In a certain region of the San Joaquin Valley, for instance, no farmer, even today, plants his cabbages without first consulting an almanac!
Consider the Moon and the weather. We are told that changes in the Moon's phases—at the quarters, full and new—bring changes in the weather. Now, in the first place, the Moon could only affect the weather by variations in the amount of heat it radiates to us. There is a variation in this respect, it is true, for not only is the illuminated surface at the quarter phase only half that of the full Moon but, because of the rough surface of our satellite, this surface sends far less than half—only 1/9th or 1/10th—as much light and heat as the full Moon. But even the full Moon sends so little that it can have no appreciable effect, in fact it sends only 1/465,000th as much as the Sun. Taking the phases into account, it is found that in 13 seconds we receive as much light and heat from the Sun as we do from the Moon in a whole year! Evidently, then the Moon's heat is quite unimportant to us; a light cloud passing in front of the Sun deprives us of more heat than the Moon ever sends us. In the second place, storm centers travel across the Earth, generally from west to east in our latitudes, and can often be traced clear across a continent, or even half way round the globe in the course of a week or, two. If the storm begins with a change in the Moon at one station, it clearly will not begin with such a change at another station some hundreds of miles east or west of the first one. Finally, records kept at many stations for long periods of time—a hundred years in some instances—show no relation whatever between Moon change and weather change, tho chance coincidences are of course frequently found.
