Well! one morning when we were only a few leagues off the West Coast of Africa, to the South of the Cape Verd Islands, we thought we were going to have just such a calm as the poet has described. There had been a violent storm during the night, but every breath of wind had died away, and left a long sleepy swell upon the sea. About nine o'clock, we noticed a cloud rising, or rather seeming to form, at some distance from us, and just below it a white spot of foam appeared on the surface of the water, and the waves raged over a little round space in a way that made me feel I don't know how, for I had never seen such a thing before. The cloud grew blacker and blacker, and presently seemed to move down towards the sea and swell out in the same direction, as if to provoke the waves below, which seemed straining up towards it. WATER SPOUTS There suddenly seemed to grow out of the middle of the spot of waves, a complete pillar of water of a tapering shape, and at the same moment the lower part of the cloud seemed to condense and turn to water, and shot downwards in a cone to meet it. They united and formed one pillar, almost as distinct as if it had been of ice instead of water. You will see a correct representation of this in the picture. The size at the base must have been very large, not less than 250 feet in diameter, but it tapered off so much that at the middle it was not more than three or four feet. Above the middle it increased in size, and its solidity seemed to get gradually less till it ended in a great black cloud. Its height might have been about 700 feet. Its form changed considerably. It generally seemed as if it was composed of water sucked upwards in a spiral direction, and looked almost like a great cable; but now and then it looked like a simple hollow tube. Sometimes it inclined a little one way, and then another; and sometimes it was very considerably bent, and then suddenly straightened itself again. When the ship was nearest to it, we heard a noise from it like the rushing of a waterfall, and before it was over, heavy rain came on with lightning, but no thunder. The wind all the time was very unsteady, though it was not violent. While we were looking at it, two smaller ones formed at some distance under very nearly the same circumstances. One of them stood quite still for some seconds, and then disappeared; but the other moved steadily on in a straight line, for several minutes. The great one continued moving also very I have seen many water-spouts since, in my voyages over the great ocean, but have never been so struck with the appearance of any one as of this. There is a common notion that a cannon fired at a water-spout, will disperse it by making a great concussion of the air; but I do not think that this is true, unless the water-spout be very small. At all events, it was not true in this case, for we fired right at the large one several times, and it took no effect except in splashing the water about as the ball went through. It is also generally imagined that they are very dangerous to ships, and if they come close, that they throw such a quantity of water into them as to sink them. I have somewhere read Once I saw a much smaller water-spout on land. It was a gusty, cloudy day, and the wind had changed several times, when a dark cloud at some distance from where I was, extended downwards till it came nearly to a point. It seemed to reach about three-fourths of the distance from the cloud to the ground, and moved along slowly for about ten minutes. When I afterwards made inquiry of the people over whose houses it passed, they told me that it had let fall in its progress a tremendous quantity of rain, so as considerably to injure several houses. HOW PARLEY SUPPOSES WATER-SPOUTS TO BE CAUSED. I suppose you would now like me to tell you how water-spouts are caused. I wish I could, for your sakes; and, besides, I should very much like to know myself. I have, however, a tolerable guess upon the subject, and that I will tell you of. I dare say you have often seen little eddies of wind which take up dust, straw, and other light substances, and carry them up, twirling them round in a spiral direction like a cork-screw. When these occur on a larger scale, they are called whirlwinds, and are often very destructive in their effects, unroofing houses, and doing various other mischief. They are sometimes occasioned by draughts of air being disturbed in their course by mountains or hills, and meeting each other. But the largest are caused by two or more currents of wind, produced by what ordinarily influences the direction of the wind, meeting from different quarters, and then twisting round each other just as two strings, with weights at their ends, would do if you swung them forcibly together so as to meet about the middle. A whirlwind occurred some years ago, near where I was living; it lasted about ten minutes, and produced some very curious effects. It first met with a milk-maid, who was carrying a pail of milk upon her head, and tore off her bonnet along with the pail, and carried both to a great distance, where they were not found till some days afterwards. It next twisted a wagon in pieces, and blew most of the fragments over a Suppose a cloud happens to be exactly in the point of union of two currents of wind, meeting as they did in this whirlwind, it then becomes twisted in along with them, and partially condensed; and if it is over the land, this is all that seems necessary to form the water-spout. And if it happens to be over the sea, the wind, as it eddies round, works up the waves into a ferment, and much spray and foam is produced, which is twisted in with the whirlwind in the same manner as the cloud, and carried upwards to meet it. Whether this is just the way in which the The cut will enable you to understand what I mean. The star in the middle represents the water-spout, and the three arrows the directions in which each of the three vessels found the wind come, which shows that three diverse currents of air all set towards the water-spout. |
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