Page:Popular Science Monthly Volume 67.djvu/510

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ology too was so long neglected, both in popular and liberal systems of educations. But this has changed, and now even throughout the public schools of this country the subject of meteorology has taken a firm place.

The moon was for a long time widely held, and deep in popular belief, as the great weather breeder and prognosticator. But in recent years the lunar idea of weather control has been largely discarded. This belief could hardly be considered more than a mere superstition, as it is impossible to see from an astronomical analysis how the varying positions of the lunar cusps could in any way be connected with the character of the weather.

The moon's appearance to us depends on the relative position of the moon and sun in regard to the observer's horizon. From new to full, the moon gradually increases from a crescent to a full circle, and back again from full to new. The positions of the crescent vary, as the moon (shining by the light of the sun which she reflects to us) is sometimes north of the sun's path and sometimes south of it. The variation is probably noticed most in the new moon which is seen when the sun is just below the horizon. A line joining the horns of a new moon is sometimes nearly vertical, and oftentimes nearly horizontal. These were supposed to foretell the weather, the first being called 'wet moon' and the second 'dry moon.'

Even if the several lunar phases did influence our atmosphere, the same phase should produce the same effect all around the world (as the earth revolves on its axis in twenty-four hours) for any given latitude circle. It is true that the ocean tides are for a large part the result of the moon's attraction, but this force, when applied to the earth's atmosphere, is wholly insufficient to produce any appreciable disturbance in the atmosphere. It is most probable that the moon belief grew up out of the naturally frequent coincidence between certain weather changes (and certain brands of weather) and selected moon phases. The moon enters a new phase, or quarter, every seventh day, and the weather (at least in the middle latitudes) changes on the average of one to two times in seven days; hence there must be a great many accidental coincidences. And if one counts the agreements and overlooks the disagreements, quite a theory could be announced. The lunar phase theory was not found to bear the test of accurate comparison of weather observations with the lunar phases, except in this very slight and imperfect manner, which is entirely insufficient to have any value in weather prediction. Nevertheless, the moon and her changing phases have been the basis of nearly all the weather forecasts found in the almanacs. And the almanac has probably received more wide distribution, and been more greatly cherished by the people of all countries, than any other publication, next to the Bible.