Evening star., 1896-07-04
HOW TO KNOW TORNADOEs.
some Characteristic Features OF
These unwelcOme Visitors.
From Harper's Weekly

Some Characteristic Features of
These CnwelcOme Visitors.
From Harper's Weekly.
Perhaps the most important distinction to
emphasize is that between the appearance
of thunder storm and tornado, since If
this can be defined, much needless fear at
the approach Of black but harmless thun-
Ger storms can be avoided. When not COM
biz ed with tornado manifestations the thun-
Ger storm sends aloft a narrow line Of
black clouds in advance, which remains
Elgh In the air. At the right and left the
black clouds seem to reach the earth. but
thls is caused. not by descent to the
eafth, as in tornado. but by distant edges
of the high black clouds receding below the
Iorlzon line. 1t is one storm which spreads
to the left and right. There is no splitting
up of clouds with the formation OF a off.
1eient storm at another part of the hori-
Zon.
The tornado is easily distinguished from
this perfectly plain edge of black with its
lighter rain mist extending to the earth
Whether the funnel is velled by rain or
not, II Is ordinarily SO black that as il ap-
groaches II appears as column of dense
darkness, narrowest at the EARTH with
nght breaking through on either side of It,
The most marked trait of all is that other
ciouos seem to be approaching, others NOV
ing al rig mt angles, and distinct storm of
HSht hue is coming UP from the southwest
This is all caused by the tornado which IS
drawing clouds and air currents toward
Itself from great distances. AS the oruaGo
tunnel comes nearer, with its dark mass of
RUBBISH reaching to the earth, the roar is
frightful, giving the observer fifteen or
twenty minutes warning. The southwest
corner of the cellar, if the tornado is an
preaching from the south west, is the
Safest place of refuge. The tornado carries
the wreckaSe to the Forth and east and If
the funnel is seen in the north or east IL
need not be feared. because it viii almost
certainly move away. OF 6vU tornadoes spe-
ciaily classified, all but thirty-f!ye moved
from southwest to northeast, and nearly all
the thlrty-nye moved eastwardly.
Inc tunnels have rotary motion from
right to left, and this motion is not due TO
electrical action, but to acceleration of con-
flcting air currents. Lieut.. Finley shows
that the lightning supposed to be in the fun
rel is already in adjacent thunder clouds
The broken and withered buds bruised t,y
the action of the air, are evaporated by the
Sun after the tornado. causing the foliage TO
lcok scared, giving rise to the error that the
tornado manifests burning electrical power
1t has been demonstrated by study of
Wreckage that as the funnel leaves the
earth and rises into the air its force slight
ly diminiShes, and that this bounding mo-
ton causes the funnel to spare one build
Ing and demolish another. The funnel
with Its small end to the earth spins like
top, moving along at an average rate of
about forty miles and hour. but the We
locity of the spin is incalculable 1t is like
the motion of air impelled by an explosion.
Tornadoes generally occur between D. H.
and pm, and not more than one in a
Thousand takes place between 10 pm and
noon of the following day. 1 have heard of
only two instances in which the tornado oc-
Cured between midnight and morning-one
at HohokuS. Nj, and another in southern
Michigan, which caused slight loss of life
cases, the danger from tornadoes at night
Is so small that it need not be considered.