Page:Popular Science Monthly Volume 75.djvu/478

474 unparalled brilliancy of the Dog Star, astrologists assigned to it powerful influences, and because it rose just before the sun, at the season when the Nile overflowed, it was supposed to be the mystic cause of the inundation. They gave it the name of Sirius, from the river Nile, which was called Siris in their hieroglyphics. They also called it the Dog Star because, like a faithful watch-dog, it warned them of the approaching overflow, and they waited for its appearance with deep solicitude, for on the overflow of the river depended agricultural prosperity or blighting drought. They computed the length of the year from the heliacal rising of the Dog Star and this is still known as the Canicular year. The Romans were equally solicitous and were accustomed to sacrifice a dog to Sirius, to render his influence beneficent to agriculture. Virgil says:

 Parched was the grass, and blighted was the corn: Nor 'scaped the beasts; for Sirius from on high, With pestilential heat infects the sky.

The time of the year when the Dog Star rose with the sun and appeared to combine its influence with the solar heat they gave the name "dog days" (dies canicularis) which began August 4 and ended September 14. Owing to the displacement of the constellations by precession, the time of the heliacal rising of the Dog Star is continually accelerated, hence modern dog days have no connection with this star, and furthermore, recent study of rabies proves that more dogs go mad in winter or early spring than in summer time.

A favorite prediction of astrologers was of cataclysms that would destroy all mankind. Such a catastrophe was foretold to occur in 1186, and a universal deluge was predicted for the year 1542. In the latter year there was to be a conjunction of three planets in the watery sign of the "Fishes." The prophecy was generally believed and the terror was wide-spread. A Noah's ark was built at Toulouse, but the year was distinguished for its drought.

Ridicule is sometimes more efficacious than argument in overthrowing false theories. A skit by Dean Swift discredited astrology, in England, more than all the evidence of science. Swift published a satirical pamphlet under the title of "Predictions for the Year 1708, by Isaac Bickerstaff, Esq.," in which he predicted the death of a well-known astrologer and almanac maker by the name of Partridge. He claimed to have consulted the stars and calculated the exact hour of the astrologer's demise. This was followed by a letter to a man of rank, giving complete particulars of Partridge's death on the day and almost at the very hour foretold. The angry astrologer denounced the pamphleteer, employed a literary friend to write up proofs of his existence and published his almanac for the year 1709. Swift answered all of the arguments, claiming that the denial of death was spurious, and that the deceased was a gentleman who would never have used the