Bristol news. [volume] (Bristol, Va. & Tenn.) 1867-189?, 1881-06-21
Diana's Photograph.
TIE WAY THE AsTRoN oMERs MAKE THE
INcoNsTANT MOON SIT FOR HER
LIKENESS.
Baltimore Sun.

"Do you think | don't know the emoon
from peeled Granger" was the half in
dignant, half laughing exclamation of a
young lawyer who was shown u stero-
scopic picture of the carth's satellite in
the writer's presence.
Probably he is not the first intelligent
person who has made the same mistake.
In truth, a common photograph of the
moon does bear Il striking resemblance
to a peeled orange. The great crater,
Tycho, looks like the nib whence the
stem has been removed and the long lines
of trap rock or whatever they may be,
that radate from the crater, resmblc the
whitish strcuks marking the divisions of
the orange. But in larger and better
photographs, and especially in those
taken at one Of the quarters, instead Of
mt full moon, all resemblance to an or
angc is gone. Where the line Of daylight
falls, the sauccr-shaped craters, with
their sharp central mountain peaks and
the long, Jagged shadows cast by lofty
ranges are revealed with surprising dis
dinctness.
Photographs of the moon are not mere
scientific curlosities. They not only
serve n useful purpose in Astronomical
research, but they have commercial
value. Few collections of sterosCoplc
views are destiture of one or more of
these photographs. They are as popu-
lar as pictures Of some actresses. The
way these views are obtained is interest
ing. Everybody knows that stereo-
scOpic picture Of person or waterfall Is
rot by combining two pictures Of the
object taken from different standponts,
80 that each shows n little around the
corner, and the two being combined
make the object appear to stand out in
lifeike perspective. To produce the
same effect with the moon, advantage is
taken of the fact she Yibrates, or rolls a
little upon her center, in swinging about
the earth, so that at one time we see q
little more of one side than usual, and
at another time of the other siGo. When
two photographs Of the moon taken at
oppositc vibrations are combined by the
gteroscope the lunar orb seems suspend
ed before the eyes like ball that the
hand can grasp.
America is ahead Of Europe In the art
of celestial photography. Englishmen
of science, who, like all Euglishmcn,
| have keen eve for the detection Of spc-
| cial excellence in the work of their own
countrymcn, admit this. They say that
| the photographs of the moon taken by
Mr.. Lewis NJ. Rutherford, of New York,
are better than those taken by their own
| Delaruc, who is 80 conspicuous an as
tronomer that one of the oceans Of the
planet Mars has been named after him.
Mr.. Rutherlord's lunar photographs are
so fine that they can be sufficiently mag
ni1ed to furnish better view of the
moons rocky scenery than many anna
| teur astronomers can obtain with the
power of their telescopes.
Everybody has seen what is called
"the old moon In thenCw moons arms"
| when the moon, only few days old,
appears as Il narrow crescent, the unil-
| Illuminated orb Is seen shining with u
faint, ashy light. This light comes from
| the earth, and Is reflected back by the
moon lust rs the landscape Is family Wis
ible In full moonshinc. A few week ago,
NJ. Lnnssen, of Paris, succeeded In maxi
ing photographs of the moon that show
cd this phenomenon clearly. SO light
| that sprang from the sun was reflected
| from the fields and waters of the earth
to the moon, was thrown back from her
stony surface to the earth again, and
after this triple journey yet retained
| enough power to stamp the faint picture
of lunar landscapes upon n photograph
lc plate.
Moon photographs are taken by the
aid Of telescopes, the prepared plate be-
ing fixed at the focus Of the instrument
in The place of the eye piece. they are
obtained only one or two inches IN di-
| nmctcr and have 20 be enlarged. Fine
ones will bear being enlarged to o diam-
oter of two or three feet. Mr.. Ruther-
ford uses u retracHng telescope to photo
graph the moon, the object glass being
peculiarly corrected 40 that II focuses
the acllnic rays. Most other aaironomi-
cal photographers use rejecting tclc-
sropcs, I'm which concave mirror takes
the part Of an object glass.
The moon IL not the only celestial
object whose picture can be taken. Pho
tographs are also made Of the sun, show.
Ing the spots and The phenomena of
eclpses. Venus aud Mercury have been
photographed when In transit across the
SUMS disk. Even stars can be photo
graphcd, and recently Prof Draper, Of
This city, succeeded In photogiaphlng the
Great Ncbula Of Orion, which nstrono-
mcrs believe TO be- IN enormous mass Of
gascous mattcr containing In Itself the
germs of future worlds and suns.
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