d South poles to the equatorial regions near the
surface of the earth. Thus the cold air currents, in passing from the
North and South poles, are ever passing over surfaces which are
increasing in velocity as they journey on their way to the equator. This
of course occurs all round the earth, so that the earth is continually
revolving in these currents, and if the rotational velocity of the
surface of the earth were wholly imparted to the air directly over its
surface, then the currents would be always flowing due North and South.

If, however, the earth fails to impart all its rotational velocity to
the atmosphere, or the atmosphere fails to pick up the whole of the
rotational velocity at once, then the result will be that the atmosphere
as it passes over the surfaces of greatest velocity will lag behind,
because its rotational velocity will be less than the velocity of the
earth's surface.

Now this is exactly what does happen in regard to the atmosphere, with
the result, that instead of getting winds blowing due north and south,
we get what are known as Trade Winds, which blow north-east in the
northern hemisphere and south-east in the southern hemisphere. Here then
we have direct experimental proof on a large scale of the very principle
I have stated, viz, that a medium surrounding any rotating body does not
move through the whole of its extent with the same velocity as its does
at the surface. Thus it can be seen that the velocity of the rotating
Aether will be greatest at the surface of the sun, but its angular
velocity will decrease the further the medium recedes from the sun.

The same principle can easily be proved from an electrical standpoint;
for if we consider the Aether currents as electric currents, no one
would think of suggesting that the intensity of the currents was the
same at a distance of several million miles away, as it is near the
source of the currents, which in this case may be looked upon as the
sun, because at its surface we have the greatest electric potential
(Art. 80).

So that we see from this reasoning, that not only is there a decreased
mass of the Aether at the distance of Venus, compared with Mercury, but
there is also a decreased velocity in the rotatory electro-magnetic
Aether currents, with the result that the impressed force exerted upon
Venus is less than the impressed force exerted upon Mercury, and
therefore Venus should move slower through space than Mercury, which is
exa