4 8o THE POPULAR SCIENCE MONTHLY. 



of plants and animals, it is the case that the only wide rules for pre- 

 dicting 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 as- 

 trologers, 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 predic- 

 tions." Bacon remarks again that reasonable astrology (Astrclogia 

 sana) " should take into account the apogees and perigees of the 

 planets, with a proper inquiry into what the vigor of planets may per- 

 form of itself ; for a planet is more brisk in its apogee, but more com- 

 municative in its perigee : it should include, also, all the other acci- 

 dents of the planet's motions, their accelerations, retardations, courses, 

 stations, retrogradations, distances from the sun, increase and diminu- 

 tion 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 differ- 

 ent manner." 



It is a remarkable circumstance that systems of weather predic- 

 tion 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 in- 

 vented in earlier times. Within the last twenty years, for example, 

 methods of prediction based on the moon's movements, on the con- 

 junctions of the planets, and on other relations, have been maintained 

 with astonishing perseverance and constancy, in the face of what out- 

 siders 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 



