44 W. Ferrel— Cyclones, Tornadoes and Waterspouts. 
are so strong as to draw in and carry up very heavy bodies and 
hrow them out above to a great distance. Sometimes the 
ascending current is so strong as to keep a heavy body sus- 
pended in the air for a long time until the tornado has pro- 
gressed many miles, when, after the violence of the tornado 
begins to abate, the body falls to the earth. Unless the strength 
of the ascending current is sufficient to carry the body up to an 
altitude where the air tends outward from the center, the grad- 
ually indrawing currents below that altitude keep the body 
near the center and it cannot fall to the earth until the ascend- 
ing A aie! of the current which has carried it up, is dimin- 
ishe 
Waterspouts.—These are simply special cases of tornadoes, as 
tornadoes are of cyclones. Where the air at the earth’s surface 
in a tornado is not nearly saturated with moisture, it has to 
ascend to a much greater elevation on the outward border of 
the tornado before cloud-formation takes place, and also the 
nearly horizontal inflowing and gyratory currents below have 
to approach very near the center before cloud is formed, 
and the nearer the earth’s surface, the nearer this approach must 
be. Hence, the base of the cloud assumes a funnel-shape 
above, with a long tapering stem reaching down to the earth or 
sea. A waterspout, therefore, is simply the cloud brought down 
to the earth’s surface by the rapid gyratory motions near the center 
of a tornado. is may be explained by means of a deep vessel, 
instead of ashallow basin, of water with a hole in the center of 
the bottom. If the water is allowed to run out, and it has only 
an almost perceptible initial gyratory motion, it finally runs 
into very rapid gyrations around the center, and the surface of 
the water and each of the strata of equal pressure under the 
surface, assume a funnel shape at the top and extend down to 
the bottom, even within the hole, in the form of a long, tapering 
tube. It is the same in the case of the air ina tornado. The 
fact that the air of the lower strata runs upward through the 
upper strata, instead of downward through the bottom, does not 
alter the case, for the gyrations, upon which the lowering of the 
strata of equal tension and temperature depend, are produced 
just the same in both cases. The stratum of the air, then, of 
which the tension and temperature are such as to condense the 
moisture of the air, assuming this shape, of course the base of 
the cloud assumes the same. If the dew-point of the air at the 
earth’s surface is . below the temperature of the air, 
then air at the outer limit has to ascend about 1,000 meters 
before cloud-formation takes place, and this determines the 
height of the spout. The distance from the center at the base, 
at which condensation and cloud-formation takes place, depends 
upon the rapidity of the gyrations, and this upon the amount of 
