And now I descry a faint purplish hue upon the red beach which lies at the foot of Culver. To-morrow, we will breakfast early, and hunt up a score of pebbles before the day grows hot.
[3] “Mémoires de l’Académie des Sciences.” Anno, 1721.
CHAPTER VIII.
PNEUMATICS AND HYDRAULICS.—POWER OF THE WIND.—POWER OF THE WAVES, AND VELOCITY ACQUIRED BY THE WATER.—OCCASIONAL HEIGHT OF TIDES.—TIDAL WAVE.—CURRENTS.—TIDAL PHENOMENA ON THE ISLE OF WIGHT.—VARIATIONS IN THE COAST-LINE.
The elemental powers which are constantly at work in Nature all around us are upon a vast scale; a scale, in fact, which is immeasurable by us, except when observed under certain favourable circumstances. As our practical ideas of locomotion are immensely surpassed by the speed of the Earth’s rotation on her axis, which is at the equator rather more than 1000 miles an hour, and yet far more surpassed by the rate at which she moves in her orbit round the Sun, which exceeds 20,000 miles an hour, so also our experience of a puff of wind on the hillside, or a dash of water in our face, when a slanting shower or the spray from a cataract salutes us, gives us no conception of the stupendous powers which are exerted when the sea, convulsed by a storm, rages along some unprotected coast.
Once in my life, I remember being knocked down by a blast of wind; and several times, as I suppose has happened to many persons, I have been floored by an unexpected billow while bathing. I always made this reflection at the moment: “Its power is not known: it has floored me easily enough, but perhaps it would have felled an ox.”
But a wave impelled by the gale, which could take an ox off his legs, is nothing at all. What is the measure of force actually applied when a stout ship is shivered on a lee shore? No one knows. When the Clarendon, West-Indiaman, struck on that fatal “race” off Blackgang Chine, she went utterly to pieces within seven minutes! Yet, what a delicate thing is AIR! What a yielding thing is WATER! But then the air and water threw her on a lee shore.
Observations, carefully made at the right time and place, enlighten our ignorance upon all these matters. Air, delicate as it seems, when compressed, explodes in the roar of the thunder; and water is almost incompressible, and therefore its blow will knock down anything.