Page:Journal of the Asiatic Society of Bengal Vol 29.djvu/408

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370
Notes upon some remarkable Waterspouts.
[No. 4,

in the centre, plainly showing it to be a solid cylinder; as it neared the earth, the lower half of this elegant column commenced to gyrate rapidly, the lower end oscillating violently to the right and to the left; this latter movement I imagine to be a mere optical illusion, caused by the lower end of the column revolving in a circle or large diameter; as the column neared the earth it expanded and contracted in an agitated and rapid manner about the centre into cloud-like protuberanees which partook at the sameof the motion of the revolving column.

Upon arriving nearer the earth, the end of the column parted into two slender columns about 150 feet each in length, and in this condition reached the ground.

The shape of the column was now completely and instantaneously altered; for the whole cumulus burst and was seen pouring down to the earth, not as a shower of rain but as a heavy mass of water, resembling a waterfall more than a shower of rain, that completely exhausted and brought the whole cloud to the ground in a few seconds of time.

The estimated height of the cumulus from its summit to its base was 5000 feet, and 3,000 feet in length, the whole of which mass of vapour was precipitated tumultnously and instantaneously to the ground in the shape of water.

The period of duration of the column from its first forming to its bursting, occupied about 25 seconds, and 'offered a very grand and imposing sight.

The mass of water so suddenly precipitated upon a large grassy plain, for the column burst upon the artillery practice ground, was simply to put half a square mile of country under water for about half a foot deep. This water took 14 days to drain off by the usual drainage courses of the country.

That the waterspont was accompanied by a noise I can hardly doubt, judging from the alarm exhibited by the cattle in its neighbourhood who fled in all directions as it descended. No noise was however heard from my position 1¼ mile distant.

By the assistance of a theodolite, a measured base, and observed marks upon the walls of my house, I was enabled to acccrtain that the height of the waterspout from its junction with the clouds to its