Semi-weekly south Kentuckian. [volume] (Hopkinsville, Ky.) 1883-1889, 1886-01-12
ToRNADoEs.
rhe Result OF Eight Years investigation
BY Signal Service Officer.

BY n Signal Service OHicer.
Lieutenant John P Finley. of the
Signal Corps. has been studying the
phenomena Of tornadoes for the past
eight years. Tornadoes are now SO
well understood that it is believed that
trustworthy warning can soon be sent
ont to the localities threatened. In fact.
experimental predictions have been
made for year, with good result. Ac-
ooriing 20 Lieutenant Finley. tornadoes
have distinctly marked characteristics
and are by no means to be confounded
with hurricanes, "blizzards," cyclones
or northeasteYs. Their tracks are never
more than few hundred yards wide.
their ,otary motion, which is greatest
toward the center, ometimes reaches
the enormous rate Of 1000 miles an
hour, while thei forward movement,
always from southwest TO northwest,
ordinarily doe not exceed forty or fifty
lniles. They are usually unaccompa :
led by electrical disturbances and are
believed 10 be uninauenced by electrical
conditions, though violent thunder
storms sometimes follow them o few
miles away.
There is distinct and curious rela-
tionship between the tornado and the
general storm center, which is always
apparent in their uniform relative po-
sitOns, the tornado always occurring
enthusiastically from the center Of low
barometric pressure, and at q distance
of from one to six hundred miles. The
shape Of the general storm center, the
direction in which its lowest barometer
lies and the appearance Of the upper
and lower clouds enter as minor eIe-
ments into the problem out of which
the weather experts hope 10 work
complete system of tornado warnings.
The visits Of the tornado are common
ly between the hours of two and six
o'clock in the afternoon. Its home is
an area which includes the whole Of
Iowa, all Of Missouri, except the south
eastern corner, the northwestern corner
of Arkansas, the northeastern part Of
the Indian Territory, Eastern Kansas,
Eastern Nebraska, Southern Mlnne-
sofa, Southern Wisconsin and Western
Illinois. Here its season extends from
April to August inclusive. 1t is also
frequent visitor to two other regions.
These are, first. strip along
the Gulf and South Atlantic coasts,
which takes in the central portions Of
Alabama, Georgia and South Carolina,
with termini in Mississippi and North
Carolina, over which It's devastations
are confined to the months of January,
February and March. The second in
cludes portion of Southern and Cen
tral Ohio, large portion Of Pennsylva-
MIA. a small area in Maryland, strip
across New York and corner of each
OF Massachusetts, and Connecticut,
whore 1t is in season only during Au-
gust and September.
The conditions which are favorable
to the creation of tornadoes are present
when cool, dry current Of air meets
warm, moist current, bringing wide OK
tremes both of temperature and hu-
midity into close proximity. The cool.
dry currents come from the north, but
such as flow over the Great Lakes pick
up in their course both moisture and
heat and their destructive forces are
thus neutralized. Those blowing from
the Northwest, down over the dry
plains Of Manitoba and Dakota, carry
something of their Arctic character
istics far South, and il in their course
they meet one of the heat
and vapor, laden breezes COM
ing up from the Gulf the war
Of the elements begins at the point of
contact. The storm always has its
birth in the upper air Its first visible
manifestation being the ominous fun
nol-shaped cloud, whose pendant trunk
Is In form not unlike that of an ele-
phant. Within It the furies are confined,
and when and where its point touches
the earth the path Of destruction be-
gins. When the isothorm Of the morn
ing signal map shows the advancing
columns Of air. with their wide con-
trasts of temperature, in proximity;
whom the general storm center is In
that relative position which seems
necessary to the exercise Of its myste-
rious influence; when the pressure Is
low toward the east, disclosing
vacuum into which the DETECTED cur
rents may advance without obstruc-
tion--when all these conditions combine
1t should become but simple problem
for the experts to determine with fea.
sonablo probability from the wind ve-
locities whether the threatening line OF
contact will have advanced to or beyond
the tornado's accustomed baunts by the
time of day when the powers of mis-
chief shall be loosed. Washington Cor.
RhiLadelphid Times. ~.