The Bottineau courant. (Bottineau, Bottineau County, N.D.) 1895-1929, 1903-08-14
u |, |, l)PE @ | I: OR AFRICA

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Desosi Dtio1n of Instrument to
Be Mounted at lBulswayo.
LEeH In WEIaH HI, But DURABLE,
It II Very similar to Those In Uae
nt GeorEetosyn University and the
I United states Naval Observatory. $.
Results OF Observation to BE Sent
to wa shing ton Before Gives, to the
Woriil.
South Africa Will shortly have one of
the finest telescopes in. the world, says
the Washington Post. This magn,f-
cent instrument was bui1t in Washing
ton. It is constructed much on the
same lines as those at Georgetown uni
versity observatory and the United
States Naval observatory 1t is the
same size optically. the object glnss
having an aperture Of twelve inches.
However, as the latitude of Bulawayo,
Rhodesia, for which place the instru-
menfis intended, is 20 degrees so'lth
Instead Of nearly 40 degrees north. as
the s5bcation in Washington. the III
rangsment of the instrument is neces-
.sarilE differant. The focus is five feet
shorter. and on this account the mount
ing is lighter.
This telescope is very rigidly built
although mere weight was not the OBJ
jectsseugEt The telescope tube weighs
about one ton, and about 5000 pounds
are moved when the instrument is
tusndl in right ascension. 1t consists
of a heavy iron pillar. on top Of which
and 3 declination axes. The former
points to the pole, and it is made to rD
tate by means Of clockwork at the exact
rate tie stars move, so that If q star be
Brought into the field Of the telescope
it .can be Ike .ot in view for hours, as the
check moves with the utmost regularity.
Should q ny deviation occur on account
sitions this is instantly corrected by an.
ingenious Arrangement, called the con.
troll which is affected electrically and
governed by the standard clock Of the
observatory that moves easily with the
stars. The two axes Of the instrument
the polar and the declfnat ion -are
sprovided with circles used to point the
Estelescopes to certain position in the
sky. and the fine graduations can be
read from the eye end by means OF mi
croseopes. For approximate and more
rapid setting these circles are also pro
xided with coarse graduations which
/ can be seen with the naked eye.
ss There is another arrangement, how
which enables the observer to set
rtfla sksscobs 81: w:tlaout looking at the
circles and without calculating the
hour angle of the object sought. This
consists Of two dials placed at the
south end of the pillar at the height
of the observers eye The two axes Of
the instrument are geared down and
end in two hand wheels: by turning Ell
ther of thes" the motions are indicated
on the dials. Each dial hand moves at
double the speed of the corresponding
axis. The declination dial is figured
from naught to ninety degrees each
way. the smallest space being one de-
gree. The right ascension dial has FIVE
second spaces and is driven by an or
binary eight day clock. AS the dial
turns with the star and the hand with
the telescope. this arrangement per-
mits to set by right ascension Instead
Of calculating the hour angle. which
consumes much time. Notwit thstand-
ing the large number OF gears involved
in driving this mechanism. the total
back lash is SO small that a star Of
known co-ordfnates is brought near the
center Of the findings at once. George
N. Saegmuller Is the inventpr Of this
valuable instrument He planned it in
/ 1888, and few years later he placed II
in the great Denver telescope Of TWEEN
| ty inches aperture, built In Washing
ton. 5 =, ..s e
The lightness Of this South African
telescope Is remarkable, while at the