Picture - Cosmic Polymath

lo DESIGN IN NATURE
PREVALENCE OF SPIRAL ARRANGEMENTS ON A GRAND SCALE IN THE
PHYSICAL UNIVERSE
The spiral formations of the physical universe are seen in whirlwinds and spiral sandstorms, in whirlpools and
spiral waterspouts, in spiral nebular arrangements, &c. In all these cases, the atoms, molecules, and bodies concerned
are arranged spirally. Winds occasionally blow in straight lines, but for the most part in curves, circles, and
spirals. The cyclone, one of the most powerful and violent of winds, pursues a circular path. When, however, it
advances rapidly it follows a rotatory, spiral course.
" It appears from recent investigations, that hurricanes, tornadoes, and typhoons are to be regarded as great
whirlwinds in motion, the meeting of two opposing winds producing the whirlwind. According to M. Dove, the
rotatory motion of the air is from right to left in the northern hemisphere, or in the direction opposite to the hands
of a watch ; from left to right in the southern hemisphere, or with the hands of a watch ; gusts and lulls occurring
in the vortices. It is further ascertained that the northern hurricanes travel in an oblique direction from the equator
towards the north pole, while the southern hurricanes travel more obliquely from the equator towards the south
pole. We frequently observe in serene hot weather the whirhng motion of the air, betrayed by sand and dust
ascending in spiral columns. Larger and stronger whirls carry up leaves and straws, and even buildings lying in
their course. These whirlwinds are generally caused by the struggle of two winds meeting at an angle, in the same
manner that eddies and whirlpools are formed in water, by two currents being obliquely impelled against each other."
There is reason to believe that whirlpools in water, and also in air, may take place without the intervention
of two opposing currents meeting each other obhquely. An artificial whirlpool is readily produced by placing water
in a circular hand basin provided with a circular aperture and plug at the bottom. If the plug be withdrawn, the
water, in its attempt to escape, invariably forms a tiny eddy or whirlpool. Circumscribed empty spaces favour the
formations of vortices and whirlpools.
The peculiar circular and spiral movements of the wind are well seen in certain sand-storms. In various regions
of the earth, more especially in warm climates, the sand is raised by the action of the wind in spiral eddies, which take
an upward direction, and form a more or less dense column of sand, having a vertical measurement of anything
up to a hundred or more feet. The column is distinctly spiral in its configuration, and spreads out at its summit,
when the sand-storm ceases. Occasionally a large number of spiral columns may be seen at the same time, arranged
in a circle.
In such cases each column rotates, so to speak, on its own axis : the whole careering round in a circle or spirally
as indicated by the arrows in Fig. .3. The movements somewhat resemble those of the earth round the sun.
Vortices occur on sea, on land, and in the heavens. At sea, and in great fresh-water lakes and rivers, they take
the form of eddies, maelstroms, and spiral water-spouts ;
on land they are seen as whirlwinds of sand, leaves, straws,
and other light substances. In the heavens the nebulse are, in certain cases, arranged in great whirls composed of
right and left-handed spirals.
The water-spout provides one of the most wonderful displays of spiral molecular action in nature. The spiral
is generally single. The water-spout consists of a huge, vertical, spiral mass of watery vapour, sometimes stationary,
and sometimes spirally moving along the surface of the water (sea, lake, or river). It descends from the clouds,
or rises from the water, in gigantic spiral wreaths, and forms a vertical spiral column from 800 to 2500 feet high
the column is also of a sand-glass shape, that is, it spreads out above and below, and is comparatively narrow in the
middle. The effect is to draw up immense masses of water into the clouds, the clouds driven by winds carrying
the moisture which they contain to large areas of the earth's surface, on which it is ultimately deposited as rain,
sleet, hail, or snow.
The surcharged clouds are the great irrigators of the land, and wherever rains are plentiful, plants and foUage
are abundant and luxuriant. The abundance of plant life in turn secures a plethora of animal life ; plants, in the
great majority of cases, supplying the food of animals ; and animals thriving and multiplying in proportion as
forage, succulent grasses, leaves, vegetables, and fruits abound.
The water-spout sometimes breaks out with terrific violence far inland. It is variously described. According to
one authority (" Descriptive Atlas," by Milner), " whirlwinds usually form a double cone ; the upper cone with the
vortex inclining downwards, while the point of the lower cone is directed upwards. In passing over the sea lakes
and rivers, the water is raised by the lower cone in a spiral column, often to the height of several hundred feet
while the clouds are brought down by the upper cone, and a water-spout is formed. Two cones have frequently
been observed to separate and re-unite ; and in the Mediterranean as many as sixteen water-spouts have been seen