El Paso herald. (El Paso, Tex.) 1901-1931, 1915-05-15
Shooting Millions Of Miles
BY GARRETT P. sERvIss.

By GARRETT T. sEhNlsS.
"HEY were telling us the other day
Of new German gun capable Of
sending projectnes across the
Channel into England. a distance OF Is
or 80 miles We have also heard much
OF the marvellous shooting OF the ar
uIiery OF the allies, which hits marks
lnat the gunners cannot see. The a.un
Is set an an elevation determined by
previous calculation. based upon the
known distance and direction OF the in
visible target, signal from an aero
plane tells when to shoot and the great
gun drops its prOjectile on the selected
point SKATERS trench, and reveals its
hidden quarry in the form Of fIvin~
fragments in the air.
Ihere IS a close analogy between
lnls work Of the big guns and that
OF the astronomer with his great
telescopes The scientific gunner in the
S EoSeIFs .IoIy also Ilnds his aim by calcu-
latlon- instead of BY sight. What he is
shooting att in the sky is generally
something that he cannot see before he
hlts II People whose idea about tel
eScopes are based upon the use OF spy
glasses have no comprehension Of ne
way the astronomer goes 10 work Win
ms huge optical ordnance
lie does not peep out Of the observa-
tory dome, fix the direction OF a star
with his eye. and then turn his teIe-
-@A'~ AAlN-A A. AA the contrary he
proceeds very much as the gunner be-
hind the lines in France or Flanders
proceeds He begins by getting the d.
rectlon and the range out Of a book or
a paper he doesn't even glance at the
SKY; he looks at the figures and then
he turns thumbscrews and handles and
squints through microscopes fixed over
sliding scales and graduated circles
until he has swung the great teIescone
tube on its nOiseless bearings which
10 nHaaH# 81
powerful and rigid in material and
construction, TO the exact pointing in
rlght ascension" and -declination'f re-
CURED TO hit the spot in the starry
vault for which he is searching
That done he puts his eye at the eve
piece, or ocular, OF the telescope and
the object that he Is after leans into
sight before him. whether it be a new
comet or double star, or a variable
star. or one Of those marvellous spiral
neoulae. which crawl in the profound
ing with his telescope. He is as
cephaloDOda, spawning the glitterinr
germs OF new suns and solar systems
The astronomer does not see the sky
when he is in his observatory. work
ing with his telescope. HIRE is as
blind TO the universe as is the steers
man Of a submarine to the broad face
of the ocean The narrow slit in the
observatory dome. through which the
long tube Of the telescope almost
GAAleA 1ESs MASu duONe MS mead. is his
only periscope. and that he rarely uses.
for his tables Of figures and his grad
uated and movable circles are all that
he needs for subcelestial navigation
often when he comes out from the
confinement Of the dome into the
fresh air, under the vast star-spangled
vault Of night. he looks up with ad-
miratiOn, and a sense OF refreshment- /
and Of inspiration, at the sight OF all
that sparkling multitude, as il it were
to him novel spectaclet
In the increase of range the tele-
scope is again like the cannon The
great gun shoots farther in proper
ton as it is able to Withstand more
and more pressure from the powder
gases, The great telescope reaches
deeper into the universal space in pro-
portion as its lenses or its mirrors are
able to collect and bring TO a focus
more and more light.
How far can a telescope see2" is
a question often asked. In order to
give an approximate answer we must
make certain assumptions. A sixth
magnitude star is at a distance OF
tial object visible 10 the naked eve
Now, il appears that the average sixth I
magnitude star is at a distonce Of
about 3l5 ught-years. or say, in round
mum 5ers. 2.175 million-million miles
Let us take that distance, then, as