WATERSPOUTS. 265 



appearing to descend from the clouds, but by closely examining it with a 

 telescope it will be seen that the motion is upwards ; the moisture in the 

 rising air becoming condensed lower and lower down, thus making it 

 appear to be actually descending. 



The area from the North coast of Cuba to lat. 40° N., between the 

 United States coast and Bermuda, is pre-eminently a region where Water- 

 spouts are liable to occur. This is owing largely to the warm moist air 

 over the Gulf Stream, and the cool dry air brought over it by the North- 

 westerly winds coming off the coast. 



(212.) Marine Waterspouts, therefore, are caused by the action of atmo- 

 spheric currents. Malte-Brun thus describes them : — " Underneath a dense 

 cloud, the sea becomes agitated by violent commotions, the waves dart 

 rapidly toward the centre of the agitated mass of water, on arriving at 

 which they are dispersed into aqueous vapours, and rise whirling round, in 

 a spiral direction, toward the cloud. This conical ascending column is met 

 by another descending column, which leans toward the water, and joins 

 with it. In many cases the marine column is from 50 to 80 fathoms in 

 diameter near its base. Both columns, however, diminish toward the 

 middle, where they unite; so that here they do not extend more than 3 to 

 4 feet in diameter. The entire column presents itself in the shape of a 

 hollow cylinder or tube of glass, empty within. It glides over the sea 

 without any wind being felt ; indeed, several have been seen at once fol- 

 lowing different directions. When the cloud and the marine base of the 

 Waterspout move with unequal velocities, the lower cone is often seen to 

 incline sideways, or even to bend, and finally to burst in pieces. A noise 

 is then heard, like the noise of a cataract falling in a deep valley ; light- 

 ning frequently issues from the very bosom of the Waterspout, particularly 

 when it breaks, but no thunder is ever heard." 



In order to prevent the danger which a vessel would be exposed to by 

 coming in contact with these tremendous columns, it is the practice, where 

 possible, to discharge upon them a cannon-ball, which, passing through 

 them, causes them to burst, and consequently removes all chances of 

 injury connected with them. This phenomenon is accounted for in the 

 following manner : — Two winds meet — a vortex ensues ; any cloud which 

 happens to be between them is condensed into a conical form, and turned 

 round with great velocity ; this whirling motion drives from the centre of 

 the cloud all the particles contained in it ; a vacuum is thereby produced, 

 and water, or any other body lying beneath this vacuum, is carried into it 

 upon the usual and well-known principle. The cannon-ball, breaking this 

 cylinder, which is always partly hollow, causes it to fall to pieces, in the 

 same manner as a touch upon the surface of a bubble reduces the re- 

 splendent mass to a drop of common water. 



(213.) The following description of a Waterspout, seen during a fresh gale 

 upon the coast of North America, was written by Mr. Murdo Downie. 



" Upon the forenoon of the 9th of October, 1795, while cruising in His 

 Majesty's ship Resolution (then bearing the flag of the late Admiral 

 Murray), in company with H.M.S. Africa, commanded by the late Admiral, 

 then Captain, Home, in lat. 32°, and long. 66^° W., having the wind at 



N. A. 0. 35 



