The Hawaiian gazette. [volume] (Honolulu [Oahu, Hawaii]) 1865-1918, 1868-07-22
Sir w. Thompson.

The discoveries of Sir VIM. Thompson II
| physical science have all been of high or
der, as he has employed a profound knowl
edge of mathematics to bring TO light many
of the laws which govern the universe. o.
late years, since more of the laws of heat
have become known to the scientific world
strong reasons have accumulated tending tc
show that the light and heat of the sun are
not caused by common combustion. When
a cannon ball strikes a target its motion Is
arrested, but heat is generated, and il has
been mathematically proved, principally by
Professor Thompson, that if a shower OF
rocks and stones was constantly falling into
the sun, the velocity Of impact would be
such that the heat generated from sufficient
quantity of such missiles would fully equal
the amount Of heat and light known by ex-
pertinent to be thrown out by the sun. lie
has calculated the quantity of heat which
would be generated by each one of the plan
cts should it fall into the sun, and proved
that the impact of the whole of them would
cause sufficient heat to cover the solar ennis
sion for hundreds of thousands OF years.
The zodacal light, that puzzle to philoso-
pliers, is believed to consist of a vast number
of cosrnical bodies, revolving round the sun
ST comparatively short distance. and con-
stantly falling upon its surface. One proof
of this is, that the planet Venus, when in a
certain position with respect to the sun and
&lc cdTlL, TcuCCts lnOTc lSul luau Ut OtucI
times. 1t also obeys the laws of planetary
motion. Meteorites and rocks are known to
be plentiful in space, especially in the orbits
Of comets; moreover, Encke's comet, year
by year, is drawing nearer to the sun, and is,
therefore, expected eventually to fall into it.
There is, therefore, reason to suppose that
the heat and light of the sun may be caused
by cosmical bodies continually striking that
luminary, and Professor Thompson has given
mathematical evidence that the supposed
cause, should it exist, is competent to pro-
duce the effect.
He has published many interesting papers
upon the rigidity and probable interior con-
struction of the earth, and he has given
great impetus 10 electrical science by unrav-
cling many of the laws which govern the
passage of electrical currents through long
cables This led to the invention, by himself
and his colleague in the Atlantic Telegraph
enterprise, Mr.. G. f. Varley, of the "curb
key" a very novel and beautiful instrument,
for working through long submarine lines.
Instead of sending, as usual, one or two cur
rents only into the line to produce single
signal at the other end, the curb key cuts the
lightning into shreds, aud throws five or
more positive and negative currents into the
cable to produce one signal. The advantage
of this method is that the many currents in
different parts of the cable when the signal
is made then neutralize each other, so that
the cable is instantly ready for q fresh signal.
Under the common system, large electrical
charge hangs in the cable for some little
time, and in long cables this charge very Sc
riously retards the speed of transmission.
Tclegraphic messages cen not be sent SO rap
idly through very long cables as through
wires of the same length supported in the
air by telegraph posts.
Sir W. Thompson also invented the reflect
ing gaivanometer, an instrument much used
L.
sages sent by very weak currents through
long cables. 1t consists of a little magnetic
needle, usually only grain or two in weight,
suspended by fibre of silk. At little dis
tance il is surrounded by coil of insulated
copper wire, SO that when a very weak cleo
trical current is sent through the coil, the
needle is slightly DETECTED. The needle has
a little slvered mirror of mica attached to
it, and as the needle moves, so does the mir
ror. OF course, messages could not be read
off by the scarcely perceptible motions of
the little magnet and mirror, so a ray of
light passing through hole is allowed to
fall upon the mirror, which reflects thin
vertical liue of light upon horizontal ivory
scale, about two feet off. Consequently, if
the mirror only move a very little, the line
of light two feet off will move great deal.
Thus the messages through the Atlantic ca
BILE are read off by watching the silent move
ments of little tongue of flame, which
travels to and fro in darkened room; and
in this manner does the Old World now
speak to the New. 1t is owing to Professor
Thompson's rejecting galvanometer that
messages can be sent through the Atlantic
cable with such low battery power; and it is
owing to Mr. Varley's Introduction of a thick
copper-conducting wire into the cable that
messages are now sent through it with a
speed which is highly profitable to the share
holders. In the face of great ridicule, Mr..
Varley for years insisted upon the necessity
for thicker conducting wires in cables, and
Professor Thompson was one of the first to
come to his support in the hard battle against
the preconceivcd notions of inferior eleetri-
cians Il Ti,e1-looI Times