246 3iE'it:ouoLt)GV. 



move one half that distance, they would not meet at the centre, but 

 pass each other at a distance of .014 of an inch, the one being on the 

 east and the other on the west of that point. These two particles, 

 as also all others which arc moving towards that point, must operate 

 as oblique forces, and though each separately considered is of that 

 order which may be denominated infinite sslmal., in their combined 

 elTect they produce a rotation from right to left depending for its vio- 

 lence upon the amount of inward pressure and the velocity of iu- 

 flux. This influx is spirally inwards as represented by the arrows in 

 Fig. 2. 



The conditions, then, of this kind of rotation are : 1st, rarefaction, 

 maintained by any cause whatever, in a body consisting of movable par- 

 ticles, such as liquids and gases ; 2nd, the free motion of these particles 

 in space, without the modifying influence of obstacles ; and 3rd, the 

 Earth's rotation. The rarefaction in the middle of a funnel is main- 

 tained by the constant descent of the fluid through the throat ; in the 

 case of the balloons alluded to by the confined hydrogen, which to- 

 gether with the materials of the balloon, constituted a light mass which 

 the surrounding denser particles were constantly displacing; in that of 

 an ordinary whirlwind, it is originally produced by heat at the Earth's 

 surface ; and in the storm-cloud it perhaps has its origin and perpetra- 

 tion in the heat given out in the cloud by condensation. 



If the explanation just offered of the facts under consideration be 

 correct, and it is difficult to offer any other which is not burdened with 

 insurmountable objections, then it follows that the rotation of fluid par- 

 ticles tending towards a common point or area in free space is a great 

 physical law. Again, if tliis law determine the rotation in the northern 

 hemisphere to be from right to left^ that in the southern hemisphere 

 must be from left to right or in the direction of the motion of the hands 

 of a watch lying with its face upwards. A scientific friend, to whom 

 this deduction of theory was stated, made arrangements with a ship 

 master, sometime since, to have it tested by observation and experiment 

 to be made during a voyage to the East Indies. If theory be sustained 

 by the facts of observation, of which there is no doubt in this case, 

 then a most important law in Meteorology will be established. And 

 hence it is difficult to escape the conclusion, that rotation must take place 

 in all cases in which there is a free flow of particles from all sides to- 

 Avards a central area either movable or stationary, and that Rcdfield's 

 theory of rotary storms is to be regarded as no longer in dispute, but 

 as belonging to our common stock of knowledge. 



