Daily globe., 1883-08-18

places the track of the cyclone was changed
so that trees quite distance to one side
of the main path were leveled to the
ground, barns were blown to pieces, and
locust grove was reduced to kindlirg wood.
The speaker asked if the section OF cleo
tricity was not an active factor in these
storms? May there not have been an un-
| usually large accumulation of electricity
in the clouds, inducing powerful earth cur
rents, where the conditions were most IA
vorable bringing portion of the cloud
down to the earth until the equilibrium is
partially restored?
THE STATIC TELEPHONE.
Prof. A. E. Dolbear next presented his
promised paper upon the static telephone,
illustrated with instruments.
ed, but it was quickly dropped from sight,
but Investigations of Sylvanius Thompson
has developed many facts which were not
previously known. In his thesis he states
that the Rice telephone was a speaking
telephone. Rice had closed circuit of
electricity-an electric magnet and a de-
wise, the latter at the terminal, thence con-
nected through battery with the ground.
strument by a blackboard drawing. This
device was invented about twenty years
ago. 1t is the same principle involved in
telephones in use at the present time. In
'76 Prof. Gray, of Chicago, described a
telephone, an improvement upon
that of Mr.. Rice, but unfortunately he
did not work It out and make it public
until Prof. Bell got a similar instrument
of Tod
what legitimately belonged to him.
Magnetism has been dispensed with. Con-
cerning his receiver, invented by himself,
the essayist wishes to call attention to
several scientific points. A ground or
return circuit is not absolutely necessary,
yet with it, stronger current is secured.
The equivalent, or nearly, is
secured in the body itself.
There is no passage from the receiving
plate to plate, there being a thin air cham
ber between, and the sound is carried by
induction. The plates will hold charges
of electricity, even when grounded, for
days and days, and because of this fact
the speaker had prepared a devise which
discharges the induction coil, so that the
instrument is always ready for immediate
use. 1t charges and discharges upon ring
call is made. The receiver is fixed with
a set-screw so that bringing
the one plate to the other stopping the
free vibration of the front plate, so mate
rally reducing the loudness of the sound.
The rods are first covered with a coating
OF parafne and then with tin foil to inso-
late them. The speaker exhibited an inge-
nious device used as telephone receiver,
rtvuhn ic oho =
it to the ear, even though not connected to
the wires or transmitters, sound can be
distinctly heard, and furthermore, you
can hear when standing upon
the opposite side of the room and not con-
nected to the transmitter. A practical
test of this combined condenser and re-
ceiver was made. The static telephone on
exhibition, being connected with the instru-
ment in the Office of the telephone in an
other portion of the building and a gen.
tleman talking into the transmitter of the
latter could be distinctly heard by the
audience across the room of the section
in session. To do this the condenser was
held toward the audience by the professor.
Induction from telegraph or electric
wires strung near the wires of this tele-
phone have very little effect. In cases
where the Bell telephone failed owing to
the confusion of sounds from induction
from other wires in close proximity, the
static had been tested and worked admir-
ably.
MAGNETIC SURVEY OF MISSOURI.
The next paper was upon the magnetic
survey of Missouri, by Prof. F. E. Nipher,
secretary of the section.
The points at which observations have
been made are about 160 in number. The
auspices have been exclusively of a pri-
vate character, and the subscriptions to
the snecessary fund for the work have
been made entirely unsolicited. The first
three years of the work was devoted
to making a preliminary survey to
established the normal condition of the
magnetism Of the state. So far IL @ sur
veys have been conducted SO as to avoid
those sections where it was well known that
very favorable conditions existed. Very
frequently local effects had to be checked
in order to arrive al normal values. The
temperature correction of the surveys have
been very carefully attended to- Charts of
the surveys were exhibited to illustrate the
paper.
1t is now established that the contour
gives no indication of the actual values.
The greatest obstacle to the work is met
IN the fact that the instruments are
necessarily entrusted to people who are
not thoroughly skilled in their scientific
uses.
WEATHER FORECASTS.
"A method of distributing weather fore
casts by means of railways" was the title
of paper read by Prof. T. G. Mendenhall.
The method was illustrated with device
of simple characters. They are put upon
the side of the baggage car of trains which
pass through valuable or rich agricultural
districts, so that the farmers may have a
simple method of receiving the intelligence
of the weather predicted by indications.
WEATHER SERVICE.
Prof. F. E. Nipher followed in a paper
upon plan for state weather service.
He suggested two lines, state central
station so that the intelligence of threat
ened storm may be communicated in both
directions from central point. As soon
as the second picket line is reached the