The Indianapolis journal., 1895-07-07

~ an electric flash is transmitted from
one end OF the country to the other.
The merchant on going TO his office after
breakfast dispatches a message TO a
place thousands of miles distant, and
easily receives his answer before the
morning Is over, Notwithstanding the
inevitable delays Incidental to the trans
mission and the reception of the mes
sage. The speed at which the current
actually travels is. indeed, so great that
very elaborate instruments are required
IL that speed is TO be measured Only an
imperceptible fraction of a second would
be occupied in an electric journey across
continent. The actual velocity at
tanned in telegraphic practice varies &C.
cording to circumstances. The cleo
trician, however, knows that, even when
all the circumstances are most favorable.
the speed of a current along a wire could
never exceed 1000 miles a second We
shall employ this maximum speed as the
velocity OF electricity in our present IL
lustration
Just consider all that this implies.
Suppose that a row of telegraph posts
$4,000 miles long were erected round the
earth at the equator. Suppose that a
wire were stretched upon these posts for
this circuit of $4,000 miles, and that then
another complete circuit was taken with
the same wire around the same posts,
and then another, and yet another In
fact, let the wire be wound no fewer
than seven times completely about this
great globe. We should then find that
electric signal sent into the wire at
one end would accomplish the seven cir
cults in one second of time. Provided
with this conception, we can now give
suitable illustrations of the results at
which astronomers have arrived in their
researches on the distances of the stars.
Let us suppose that the telegraph
lines, instead of being merely confined
1h1,
the length and depth of space. Let one
wire stretch from the earth to the moon,
another from the earth to the sun, an
other from the earth to the nearest
bright star, another from the Garth to
faint telescope star, and finally let the
wire be stretched all the way from the
earth to one of the more distant stars
Let us now see what the very shortest
time would be in which message might
be transmitted to each of these several
destinations. First with respect to the
moon. Our satellite is, comparatively
speaking, so near to US that but little
more than second would be required
for a signal to travel thither from the
earth. The sun is, however, many times
further away than the moon, and the
time required for sending a message to
the sun would be correspondingly longer
The sun is, indeed, so far that when the
key had been pressed down and the cleo
tric wave had shot forth along the solar
wire TO pursue its route at that stupend-
Gus speed which would permit it to place
girdle seven times round this earth in
a second. yet eight minutes would have
TO elapse ere the electric wave, notwith-
standing its unparalleled velocity, had
passed from the earth to the sun. An
answer sent back from the sun would
require another eight minutes for the re-
turn journey, so that, if there were no
undue delay in the solar postoffice, we
| might expect reply within half an hour
or so after the original message had
been dispatched.
Telegraphing to the stars would, how
ever, be much more tedious matter
Take first the case of the very nearest of
those twinkling points of light, namely,
| Alpha Centauri, to which / have already
| referred. The transmission of a tele-
graphic message to this distant sun
| would, indeed, tax the patience of all
| concerned. The key is pressed down, the
circuit is complete. the message bounds
| off on its journey; it wings its way along
| the wire with that velocity sufficient to
carry it $780, 900 miles in a single second
| of time. Even the nearest Of the stars
| is, however, sunk into space to dis
| tance SO overwhelming that the time re-
/ quired forsthe journey is not a question
/ of seconds, or of minutes, not of hours,
| not of days, not of weeks, nor even of
| months-for no less than four years
| trembling along the wire with its unap-
proachable speed had accomplished this
| stupendous journey.
INCOMPREHENSIBLE DISTANCES.
| Alpha Centauri is, however, merely the
nearest of these stars. We have yet to
indicate the distances Of those which
are more remote. Look up tonight to-
wards the heavens. and among the thou
sands Of twinkling points which delight
our eyes there is many one up there
so far off that if, after the battle OF
| Waterloo had been won, in 1915, the
Duke of Wellington had telegraphed the
news to these stellar depths the message
| would not yet have been received there
Notwithstanding the fact that for eighty
years it has been flashing along with
that lightning velocity which would
carry it seven times round the earth In
the interval between the two ticks of {
clock.
There are stars further still. Fortify
your eyes with a telescope and direct il
towards the sky. Myriads of stars viii
then be revealed which would not b'
discerned without it's aid. Nor need We
feel SURPRISED that the effulgence o
glorious suns as these spheres undoubt
edly are should shrink to such inconsid
erable proportions when we think of the
awful remoteness Of these bodies. Ovel
our heads there are thousands of stars
so remote that, If the news OF the discov
ery of. America by Columbus had beer
Lcirculated far and wide through the uni
Iverse, by the instrumentality Of the tele
| graph, those thousands of stars to which
I now refer are elevated into boundles
space to attitudes so stupendous that th'
announcement would not yet hay'
reached them.
And we have still one more step t.
take. Let us think of the telegraph wir
that is supposed to run from the eartl
| TO one of those stars which are onl.
known to US by the impressions the.
make on a Photographic plate. 1t seem
certain that many of these stars are s.
remote that if the glad tidings Of tn
first Christmas at Bethlehem, 1884 year
ago. had been disseminated through tn
universe by the swiftest electric curren
ever known-yet these stars are so in
conceivably remote that all the second
which have elapsed in the 1,S94 years o
our present era would not have suffice'
for the journey.
Some there are who may be inclined Z
| doubt these facts, and, of course. I
| doubt wisely is a most wholesome atti
tude to take with respect to all scientifi
work. But If any reader OF these line