Evening star. [volume] (Washington, D.C.) 1854-1972, 1892-11-19
SUPPLYING NAVAL Ships

The most complete existing collection of
portable instruments used in connection with
navigation is kept at the naval observatory for
supplying the ships of the United States navy.
II includes the finest and most costly devices of
inns oeseripnon. from small telescopes in
leather cases to the contrivance newly invented
by an officer in the service for determining the
pitch OF ship In a storm. There are small
astronomical outfits with which one may 90
ashore and set up miniature observatory at
briet notice All naval vessels that 20 to sea
must have their chronometers regulated and
tested at intervals. For this purpose a meat
refrigerator has been put into the new building
by chicago firm. The thermometers vii, be
placed In this cooling apparatus. which is of
the latest and most improved pattern, the
temperature being reduced by ice overhead to
Az degrees Fahrenheit. The ice having been
removed, the air inside the box will be
raised to 80 degrees by hot water pipes sur
rounding 1t. a chronometer which endures
such extremes of heat and cold without being
anected VIII be expected to withstand similar
lnnuences on trip from the equator to the
arctic. Each ship is provided with four
chronometers and a watch, the last being
carried IN the pocket of the navigating officer
commonly. These watches are regularly tested
Ike the chronometers. They are of American
make. 10 such point of excellence has the
manufacture Of watches in this country attained
that timepieces of this kind, costing SIG or
SIS, are found to run within fifteen seconds q
month o. absolute accuracy. Foreign watches
are not in it with them at all.
SCIENTIFIC sPECTACLFs
Astronomical science is now finding pre-
sentiment on the stage in tbs shape of what are
called scientific spectacles" or "Urania" enter
tainments. The lecturer on extra-mundane
matters carries the sun. moon and stars
around with him from city to city,
together with as much scenery as a grand
m nyNny,t C L..
This style of educational show was origi-
mated in Berlin and it has been introduced on
a larger scale in this country by Garrett 7.
Serviss, the well-known astronomer. Instead
of merely throwing msgic-lantern pictures
upon screen. scenes on the moon and other
planets are actually exhibited by elaborate
stage setting, assisted by tho finest kind of
scene painting and most ingenious mechanical
contrlvances. For instance. views on the moon
place the audience seemingly on tho very sur
face of that orb. from which the spectator looks
off and beholds the earth and other worlds shin
ing at brightest midday in sky OF inliy black
ness. This is because the moon has no atmos-
phere. the bright blue of the heavens as seen
from the earth being due to its surrounding
envelope of air. Ecipses of the sun and moon
well as many other phenomena Of nature are
shown. Astonishing!y realistic effects Of light
such az sunrises and sunsets, are produced
by means of rows of electric light bulbs
above and below the stage. Some Of the bulbs
are red. some blue and some white, and all are
controlled by single instrument in such man
ner that lunar or other landscape can be il
Illuminated by ever SO many changing hues The
sun is arc light of $4,000 candle power in
closed in an iron box and projected through
lenses upon TIE back 'drop' from behind the
latter. An eclipse is made By passing an
Opaque disc across the lens. For the moon an
arc light of only 1900 candle power is en-
ployed. Many other phenomena are illustrated
by various devices. Volcanoes seem to throw
up streams Of lava. while steam asce.ds in
clouds from a perforated pipe running across
the front of the stage. Lightning flashes WV
idly and The scene is rendered more realistic
ally appalling by peals and crashes of thunder.
which small boy creates by banging sheep
skin stretched on u wooden frame with balls Of
wood hanging against i. as to vibrate with
awosome noise. RENE DACHE.