Page:Journal of the Asiatic Society of Bengal Vol 29.djvu/397

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1860.]
Notes upon some remarkable Waterspouts.
367

was accompanied with hail, which often does accompany the dispersion of waterspouts; no one drew any water or other substances upwards, as is the case when waterspouts are formed at sea. The general length of the waterspouts seen, were a thousand feet, one however was 400 feet and another 1500, in length.

It will be remarked that those waterspouts seen near Calcutta took place during the later months of the wet or south-west monsoon, August, September, and October.

That electricity is the grand mover of these bodies I think is evidenced by waterspouts being more general in dead calms than in windy weather; the suddenness of their formation; their instantaneous dispersion when once the condensation of their vapour commences, their violent and rapid gyratory motion; their great power of destructiveness although no wind may accompany them, their peculiarity of tearing trees into dry shreds in a precisely similar manner, as a tree struck by lightning is torn and dried by the evaporisation of all particles of sap from excessive heat; the violent electrical discharges, balls of fire and hail that oftentimes accompany them; and the fact that their presence in no way affects the barometrical readings of the moment.

The favorite theory regarding the formation of these phenomena is simply, that when the elecrtical tension of the clouds is very intense, the powerful action that arises from this state of tension causes the cloud to lower itself towards the earth, for the purpose of discharging its electricity; this sudden rush of the cloud and its contained electricity towards the earth together, compose the waterspout: during their descent, from some unknown cause, a violent gyratory motion takes place, light substances are attracted upwards, and those whose weight prevents their leaving the earth, such as trees, houses, haystacks, &c., are torn and shreded to pieces; should the waterspout meet with water, it is immediately entangled in the gyratory motion and drawn upwards, as was the case some years ago at Cuttack, where numbers of small frogs and fish, drawn up with the water from a tank, were precipitated from the clouds and were collected alive from the roofs of the houses in the station.

Man has learnt, in a great measure, to disarm the lightning of its dangerous power; he has learnt how to avoid and not only to avoid,