The evening Argus. [volume] (Rock Island, Ill.) 1861-1871, 1862-01-02
LETTER FROM OUR WASHINGTON
CORRESPONDENCE.
W ASHlNGTOE, ID. T.,
IL Oh 1911

Dec. 9TH, lSbi
DEARS SIR :-Christmas passed very quietly
here, beside the usual services III those church.
es which observe the day, the occasion was
unnoticed in any public manner.
One among the many interesting features
Of Washington is the National Observatory,
well worth the attention Of the curious or
the scientific visitor 1t il situated on the
banks of the Potomac, southeast Of the
White House and about hall mile distant.
The site is beautiful one the view com
handing Washington, Georgetown and the
Potomac, extending as far down as Fort
Washington, opposite Mount Vernon.
The observatory itself is neat simple two
storied brick building succeed, surmounted
by large cupola, and with two small wings
extending on either side, one connecting it
with the residence of the superintendent
The different appointments contain many in
teresting astronomical instruments, which
will well repay inspection. Our attention is
first drawn to the large telescope, called the
Equatorial, a fourteen feet Retractor, with
nine inch object glass. 1t is mounted in the
large revolving cupola or dome on the top of
the building, and by some ingenius mechan.
ism is so contrived, that directed to star in
the morning. it may be left alone, aud on ex.
animation in the evening it will be found
still directed toward the same star, having
followed its pathway throughout the whole
day. Its concentrating powers are SO great
as to render distinctly visible the stars, at
high meridian. In room below are found
the meridian and mural circles In another,
the transit instrument; in another, the prime
vertical, and in another still, the great refrac.
ton circle, from Munich, one of the finest of
its kind yet manufactured So great is the
delIcacy Of its construction. the accuracy of
its adjustments, and the extreme exactness of
its performance, that the heat Of the obser-
said to effect it to such a degree, as to be one
Of the prn clpal sources of error in the calcu.
lations for which it is used.
Another Wonderful instrument is the
bhc ihNchtioh vi Ut.
Locke, of Cincinnati. 1t is so arranged that
by means Of an electrical battery in the same
building, its ticks may he heared IN any sec.
ton of the country to which the magnetic
wires lead, if in connection with the instru.
ment. Thus it may be made to record the
time in such manner, that the astronomer
in Boston, Chicago, San Francisco or else.
where, will know the hour as well as one who
stands before clock. The Observatory reg.
ulates Washington time, by the falling of a
ball At ten minutes before noon, mean
time) large black ball is hoisted to the flag
staff that surmounts the cupola. This is to
notify those who wish to get the exact time,
TO look out. At twelve precisely, the ball
drops. The younger Adams, warm friend
Of the observatory, it is said was very fond
Of watching the falling Of the ball, frequent.
ly walking the whole distance from his lodg.
Sgs to the observatory for the purpose.
eIe also chronometers for the use of the
lrnment, are kept for the purpose of test
them before purchase. They are put on
II for one year, during which, they are
Iily compared with the great astronomical
ioek. A record is kept and if they fail to
$3.50 up to the test, they are returned to the