Page:Popular Science Monthly Volume 3.djvu/494

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THE POPULAR SCIENCE MONTHLY.

of plants and animals, it is the case that the only wide rules for predicting weather were based on the motions of the sun and moon, the planets and the stars. It must be remembered that even astronomers of repute placed faith, until quite recent years, in the seemingly absurd tenets of judicial astrology. We cannot greatly wonder, therefore, if the more reasonable thesis, that the heavenly bodies determine weather-changes, was regarded with favor. Accordingly we find Horrox, more than two centuries ago, drawing the distinction here indicated, where he says that, in anticipating "storm and tempest" from a conjunction of Mercury with the Sun, he coincides "with the opinion of the astrologers, but in other respects despises their more puerile vanities." We find Bacon in like manner remarking that "all the planets have their summer and winter, wherein they dart their rays stronger or weaker, according to their perpendicular or oblique direction." He says, however, that "the commixtures of the rays of the fixed stars with one another are of use in contemplating the fabric of the world and the nature of the subjacent regions, but in no respect for predictions." Bacon remarks again that reasonable astrology (Astrologia sana) "should take into account the apogees and perigees of the planets, with a proper inquiry into what the vigor of planets may perform of itself; for a planet is more brisk in its apogee, but more communicative in its perigee: it should include, also, all the other accidents of the planet's motions, their accelerations, retardations, courses, stations, retrogradations, distances from the sun, increase and diminution of light, eclipses, etc.; for all these things affect the rays of the planets, and cause them to act either weaker or stronger, or in a different manner."

It is a remarkable circumstance that systems of weather prediction based on such considerations were not quickly exploded, owing to their failure when tested by experience. Yet singularly enough it has scarcely ever happened that any wide system of interpretation has been devised, which has not been regarded with favor by its inventor long after it had been in reality disproved by repeated instances of failure. This remark applies to recent systems as well as to those invented in earlier times. Within the last twenty years, for example, methods of prediction based on the moon's movements, on the conjunctions of the planets, and on other relations, have been maintained with astonishing perseverance and constancy, in the face of what outsiders cannot but regard as a most discouraging want of agreement between the predicted weather and the actual progress of events. Here, as in so many cases of prediction, we find the justice of Bacon's aphorism, "Men mark when they hit, and never mark when they miss."

It is noteworthy, indeed, that the very circumstance which appears to present a fatal objection to all schemes of prediction based on the motions of the celestial bodies, supplies the means of imagining that