WAVE

Mr. Boyle has proved, by a variety of experiments, that the utmost force of the wind never penetrates deeper than six feet into the water; and it should seem a natural consequence of this, that the water put in motion by it can only be elevated to the same heighth of six feet from the level, of the surface in a calm. This six feet of elevation being then added to the six of excavation, in the part whence that water was raised, should give twelve feet for the greatest elevation of a wave, when the heighth of it is not increased by whirlwinds, or the interruption of rocks or shoals, which always gives an additional elevation to the natural swell of the waves.

We are not to suppose, from this calculation, that no wave of the sea can rise more than six feet above its natural level in open and deep water; for some immensely higher than these are formed in violent tempests, in the great seas. These, however, are not to be accounted waves in their natural state; but they are single waves composed of many others: for in these wide plains of water, when one wave is raised by the wind, and would elevate itself up to the exact heighth of six feet, and no more, the motion of the water is so great, and the succession of the waves so quick, that during the time wherein this rises, it receives into it several other waves, each of which would have been of the same heighth with itself. These accordingly run into the first wave, one after another as it rises: by this means its rise is continued much longer than it would naturally have been, and it becomes accumulated to an enormous size. A number of these complicated waves arising together, and being continued in a long succession by the duration of the storm, make the waves so dangerous to shipping, which the lailors, in their phrase, call mountains high.

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