Page:The ocean and its wonders.djvu/115

 have a furious hurricane rushing perpetually round the globe at the rate of one thousand miles an hour,—ten times the speed of the most violent tornado that has ever carried devastation over the surface of the earth.

The air, heated and dried as it sweeps over the arid surface of the soil, drinks up by day myriads of tons of moisture from the sea,—so much, indeed, that, were none restored to it, the surface of the ocean would be depressed eight or ten feet annually.

We do not certainly know the height of the atmosphere. It is said that its upper surface cannot be nearer to us than fifty, and can scarcely be further off than five hundred, miles. "It surrounds us on all sides, yet we cannot see it; it presses on us with a weight of fifteen pounds on every square inch of the surface of our bodies—in other words, we are at all times sustaining a load of between seventy and one hundred tons of it on our persons—yet we do not feel it! Softer than the finest down, more impalpable than the lightest gossamer, it leaves the cobweb undisturbed, and, at times, scarcely stirs the most delicate flower that feeds on the dew it supplies; yet it bears the fleets of nations on its wings round the world, and crushes the most refractory substances with its weight … It bends the rays of the sun from their path to give us the aurora of the morning and the twilight of evening. It disperses and refracts their various tints to beautify the approach and the retreat of the orb of day.