Northern tribune. [volume] (Cheboygan, Mich.) 1875-1885, 1883-12-15

care the excellent compilation by Ser |
geant Finley. of the Signal Service,
characteristics of Six Hundred lorna
does," with reference to the question OF
devising simple apparatus for saving
human life. Saving property seems to
be out of the question, as no structure
can withstand the force of the tornado
wind. Life may be saved by recourse to
underground shelters, cellars, etc., such
as have actually been built in many
places for this end. Two facts may be
quoted from the work named: First
Three hundred and forty-seven out OF
three hundred and ninety-three torna-
does Chat is, eighty per cent? origi-
mated between the west and the south
southwest points; Second-The average
velocity of progression was about one
mile in two minutes. If five
minutes warning could have been given
at any of the late tornadoes, many lives
might have been saved. If each house
hold could be warned by the continuous
ringing of a bell, for example, that a
wind of destructive force (say seventy
miles per hour and upward) was APP
preaching, and that five minutes were
available in which to seek shelter, this
WOulu De well WOrUn uOluG.
have found that it is practicable to
erect, at a moderate expense, Cess than
5000, an apparatus which would give
from three to five minutes warning to
all the inhabitants of a small town, by
the firing of a cannon, for Instance; and
in addition, and without any increased
expense, this apparatus could ring a bell
in every house. The additional ex-
pense to each house would be less than
ten dollars, the cost of maintenance
would be less than one hundred
dollars a year, and the work would be
done by an intelligent person. The
system, for small town, would be
something like the following: Suppose
circle described about the town with a
radius of from two to two and one-half
miles. The only serious danger from
tornadoes is to be feared from the part
of this circle between the west point
and the southwest point. Along the
circumference of this circle, between
the south-southwest and west points,
run line of single telegraph-wire on
twenty posts to the mile, and from the
west point bring the wire into the town,
letting it end at the telegraph Office. 1t
is grounded at each end of the line, and
at the telegraph office it is connected
with battery, which sends constant
current over the line. Within the town,
connection is made in various houses
with magnets. Each magnet holds a
detent, which prevents bell from being
rung by the action of cheap clock
work governed by coiled spring. II
the circuit is broken anywhere in the
line, each bell begins to ring, and con-
tinues to sound till its spring is run
down; for four or five minutes for ex-
ample. A cannon could be fired by a
simple device, which would warn per-
sons in the fields, etc., to seek shelter.
In large town the circuit might end ir
one of the engine-houses of the fire de-
partment, and ring a bell there. This
would be the signal for the man or
watch to repeat the warning simulta
neously through as many local circuits. al
desirable.
1t remains to indicate the way IL
which the circuit is to be broken by thu
wind. The circuit of telegraph pole
from the south-southwest to the ives
points would contain about fifty poles
On every one of these the wire wOult
run first to an insulator, then to al
iron horizontal axis screwed into tn
side of the post. On this axis piece o
board one foot square can revolve freely
An iron rod projects below this board
and from the lower end of it SINAI
wire goes to pin in the telegraph-pole
This pin is connected by wire to secon
:asulator. From this the line goes t
tie next pole, and so on. The circul
ordinarily passes to the first insulation
thence to the iron rod, thence down tn
iron rod to the thin wire, through tn
pin to the second insulator, au1 SO to til
next telegraph-pole. The thin wire ia
necessary part of the circuit 1t is s
made that twill break when the pressur
of the wind on the square board is fift
pounds. The apparatus for each post
tested practically before it is set VI
This can be done at any time in simpl
manner. Whenever any single one
these boards is subjected to the pressul
of fifty pounds, its wire will be rupture'
and the circuit will be broken, thu
sending the necessary warning alor
the whole line. Ihave made one sue
Indicator, which is connected with
small bell in this observatory. III
wire is arranged so that it breaks at
wind-velocity of about ten miles p
hour, and it works in perfectly su
cesssul manner. The extension of Il
system for the protection of a small TOW
is aeimple matter. For a large CT
moro expensive system won
have to be provided, as the wires b
tween poles should be carried unde
ground to protect them from the chan
Of disturbance. Prof Holden 4
Science r.,
AT the Dial Verne Theatre, at Mia