The Argus. (Rock Island, Ill.) 1885-1886, 1886-02-23
TORNADO STUDIES.
AN INVESTIGATOR TELLS OF SOME
CONCLUSIONS REACHED.
Common but Erroneous Theories
Mechanical Effects in the Vortex
The Only Relief Science Can Ex-
tend-CautiOnsry Signals.

There is theory that cities are in COM
paratively less danger from tornadoes be.
cause the heavier and more durable struc.
lures may be expected to break up the cloud
vortex and thwart its fury Lieut.. Finlay,
''the tornado man" of the signal service,
shakes his head and declares that it is a great
mistake.
Recall" he says, "the visitation at Phila.
delphia only last August. The tornado
which swept through Marshfield, Mo, with
such awful consequences, would have plowed
furroE through St Louis had it struck
the city instead of the town. The greatest
structures of stone and iron will, in my opin-
ion, melt like wax in fire when the vortex
reaches them, New York, with its great en-
vironments and its millions of people may
suffer when it least expects. never see the
Brooklyn bridge that l don't think what a
| splendid target it would make for tornado
That vast framework of steel and iron will
be torn from its piers and hurled into the
| East river il the vortex ever strikes it"
Are tornadoes increasing or decreasingsn
Neither. There is no change, no pros
pect OF change, that we can see in the fire.
| quency of them or in their violence As
| this country becomes thickly settled the
| losses are greater, because there is more to
| destroy in the path. Where few years ago
the tornado cloud spent its fury on unoccu-
| pied prairies or in forests, now it sweeps over
| cities valleys and farms"
You mean TO say that you look ahead and
| figure on a specified number Of tornadoes in
given periods"
| THE AVERAGE Is MAINTAINED.
"Precisely. From the data we have we
, confidently look for about 1850 of these vista
| tons each year There are theories held that
as the western country undergoes transfer
nation through settlement the atmospheric
| conditions are changing so as TO affect the
| number and force of these whirling clouds
| Our records and observations do not show
such results
You remember, went on the lieutenant,
what took place at Grinnell, that beautiful
Iowa town. in 1872 The cloud encountered
in succession three great stone and brick
structures of the college and leveled them
with the ground Did that break up the
vortex! Not at all. The cloud swept on
with strength enough after that mighty
wrestling match to lift up a sixtv-ton engine
and a train of freight cars, scattering them
out upon the prairie 1t continued its course
for miles before it gave evidence of lessening
fury.
| No said the lieutenant, 1--WE can't build
big enough or strong enough above ground
to defy the tornado We have material evil
| dence and we have mathematical deductions
| to demonstrate this. We can figure out q
whrling velocity of 1000 miles an hour for
the movement about the vortex Conceive
of that if you can. 1t means a force equiva-
lent to our atmospheric pressure of fifteen
pounds to the square inch. Let me apply an
air pump to the capitol there and remove
this natural pressure of the atmosphere, and
how long do you suppose it would be before
that massive pile tumbled into a heapl And
vet here is an equivalent force turned loose
TO execute its freaks"
What are You going to do about it! Has
the signal service remedy"
EXPERIMENTS SUGGEST RELIEF
mot remedy exactly, but plan to warn
| people when and where tornadoes may be
expected We can not prevent destruction
of property, but we can give warning, sc
that loss of life and injury to body may be
avertedn
"This is feasible"
"Yes; we have tested the matter and sat
isfied ourselves that we can do it, For two
seasons we have been experimenting. Our
work began in March, 1884, and was con
| tinued through two tornado seasons, ending
last month. The country especially subject
to tornado formations was divided int
eighteen tornado districts, averaging about
| 100 miles square, and each Of the districts
was cut into four parts. Predictions based
on our knowledge of the prevailing condf
tons were made daily for each of these sub
divisions At first we attempted prediction,
eight hours in advance, and afterward six
teen hours The percentage Of verificatior
was IS. We sent out no warnings because
this WAS experimental work, but we are en-
tirely satisfied that we can predict and 10
cate tornadOes with considerable accuracy
The results more than satisfied us"
You would give cautionary signals o.
tornadoes to the interior sections as you d.
of storms to mariners on the lakes and or
the coastsz'
That is what We propose to do. And MOI
the least of the advantages from a system o.
| tDFHdup SlSudis VIII De tue diidy ing vi aHA
iety and fear among the people on those day
when we were able to notify them tornadoe.
Will not form. The isolated observer or com
munity can not determine or be satisfied
from limited observation as to the toruad,
probabilities But trusting to tornado sig
nails from the service, people will 60 abou
their usual occupations without continuou
apprehension, and on the days when the eau
tionary signals are given preparations car
I've made to protect life so far Us possible. ~
ST. Louis Globe Democrat