Px'ofessor Oersted on jraler-Spouts. 69 



it seems evident to me that the electricity of the water-spout 

 as well as that of the thunder-storm, is not the cause but the 

 effect of the natural phenomenon. 



The sulphurous smell which has been perceived after a 

 water-spout, would seem to be of the same nature as that re- 

 marked after a stroke of lightning. 



The sound which so often accompanies a water-spout may 

 be produced by the striking together of the hailstones ; for 

 this must here be very violent, and, on account of the proxi- 

 mity, much more easily heard than the rattling of more re- 

 mote hail-clouds. The hissing noise must occur when the 

 air is streaming into the watcr-spout from beneath. 



The circumstance that many water-spouts are often sus- 

 pended from one cloud must doubtless be explained in this way, 

 that th3 cloud is not simple, but contains as many vortices as 

 there are water-spouts exhibited. This agrees also with 

 Holm's observations made at Stockholm in 1779, when he 

 saw several clouds turned round in one vortex. 



It is plain that the whirlmnd must not necessarily remain 

 perpendicular to the earth. Hence it follows that it may seem 

 as if the upper part of the water-spout did not belong to the 

 lower. Should the oblique whirlwind raise itself and ap- 

 proach the perpendicular line, it will appear as if the upper 

 and under portions were approaching each other. \7e have 

 examples in which the water-spout has formed oval holes in 

 the earth. This must naturally have happened when the 

 whu-lwind deviated from the upright position. 



The direction of water-spouts from south-west to north- 

 east, may be ascribed to the circumstance of this wind pre- 

 ceding their occurrence. 



Water-spouts are often bent ; and this must arise from those 

 winds which prevail at various heights above the earth, and 

 which transport the enthe masses of air in v/hich the whirl- 

 winds are contained. There is nothing in such a case to pre- 

 vent one whirlwind continuing to act on the other. 



It has been maintained that sharp cannon shots can drive 

 a water-spout asunder. It is by no means inconceivable that 

 balls which strike in such a manner that their direction is the 

 opposite of the circular movement of those portions that they 



