The fancy of the Greeks delighted itself in wild visions of the height of falls. In Hesiod’s Theogony it is said, speaking of the fall of the Titans into Tartarus, “if a brazen anvil were to fall from heaven nine days and nine nights long, it would reach the earth on the tenth.” This descent of the anvil in 777,600 seconds of time gives an equivalent in distance of 309,424 geographical miles (allowance being made, according to Galle’s calculation, for the considerable diminution in force of attraction at planetary distances); therefore 1½ times the distance of the moon from the earth. But, according to the Iliad, Hephæstus fell down to Lemnos in one day; “when but a little breath was still in him.”—Note to Humboldt’s Cosmos, vol. iii.

RATE OF THE FALL OF BODIES.

A body falls in gravity precisely 16-1/16 feet in a second, and the velocity increases according to the squares of the time, viz.:

In ¼ (quarter of a second) a body falls1foot.
½ (half a second)4feet.
1 second16”
2 ditto64”
3 ditto144”

The power of gravity at two miles distance from the earth is four times less than at one mile; at three miles nine times less, and so on. It goes on lessening, but is never destroyed.—Notes in various Sciences.

VARIETIES OF SPEED.

A French scientific work states the ordinary rate to be:

per second.
Of a man walking4feet.
Of a good horse in harness12”
Of a rein-deer in a sledge on the ice26”
Of an English race-horse43”
Of a hare88”
Of a good sailing ship19”
Of the wind82”
Of sound1038”
Of a 24-pounder cannon-ball1300”

LIFTING HEAVY PERSONS.

One of the most extraordinary pages in Sir David Brewster’s Letters on Natural Magic is the experiment in which a heavy man is raised with the greatest facility when he is lifted up the instant that his own lungs, and those of the persons who raise him, are inflated with air. Thus the heaviest person in the party lies down upon two chairs, his legs being supported by the one and his back by the other. Four persons, one at each leg, and one at each shoulder, then try to raise him—the person to be raised giving two signals, by clapping his hands. At the first signal, he himself and the four lifters begin to draw a long and full breath; and when the inhalation is completed, or the lungs filled, the second signal is given for raising the person from the chair. To his own surprise, and that of his bearers, he rises with the greatest facility, as if he were no heavier than a feather. Sir David Brewster states that he has seen this inexplicable experiment performed more than once; and he appealed for testimony to Sir Walter Scott, who had repeatedly seen the experiment, and performed the part both of the load and of the bearer. It was first shown in England by Major H., who saw it performed in a large party at Venice, under the direction of an officer of the American navy.[9]