The herald., 1898-08-07

make it quite impossible for us to be
content with the rough and ready sun
dial which satisfied our forefathers,
whilst the desirability of keeping con-
stant watch on meteorological changes
so as to be able to forecast the weather
for some little time ahead will appeal
to everybody. But it was not for such
purposes as these that the Greenwich OBJ
servatory was founded in 1915. 1t was
for the rectifying of the tables of the
motions of the stars.
We have no idea who made the earliest
census of the sky. 1t is written for us
In no book; it Is not even engraved on
any monument. And yet no small por-
ton of it is in our hands today, and,
strangest of all, we are able to fix fairly
closely the time at which it was made,
and the latitude in which it's compiler
lived The catalogue is very unlike our
star catalogues of today. The places
of the stars are very roughly indicated.
and yet this catalogue has left more
enduring mark than all those that have
succeeded it. The catalogue simply con-
sists of the star names.
An old lady who attended a university
extension lecture on astronomy was
heard to exclaim: "What wonderful men
these astronomers are. l can under
stand how they can find ert how far off
the stars are, how big they are and what
they weigh-that Is all easy enough;
and l think can see how they find out
what they are made of. But there is
one thing 1 can't underestimate don't
know how they can find out what are
their names!" This same difficulty,
20 nj in a ha
old lady in her simplicity was able to
grasp, has occurred to many students of
astronomy. Many have wished to know
what was the meaning of, and whence
were derived, the sonorous names which
are found attached to all the brighter
stars on our celestial globes; Adhara,
Alderamin. Betelgeuse, Denebola. Sche-
dar, Zubeneschamal, and many more.
The explanation lies here, Some five
thousand years ago man, or college of
men, living in latitude 40 degrees north,
in order that they might better remem-
ber the stars, associated certain groups
of them with certain fancied figures. and
the individual star names are simply
Arabic words designed to indicate where
abouts in it's peculiar figure or constella-
ton that special star was situated. Thus
Adhara means "back," and is the name
of the bright star in the back of the
great Dog. Alderamin means fright
arm" and is the brightest star in the
right arm of Cepheus, the king. Betel-
geuse is the giants shoulder" the giant
being Orion: Deneboa is "lion's tail"
Scholar is the star on the breast of Cas-
siopeia. and Zubeneschamal is north
ern claw" that is of the Scorpion. So
far It Is clear enough. The names of the
stars for the most part explain them
selves: but whence the consultations de-
rived their names, how it was that so
many snakes and fishes and centaurs
were pictured out in the sky, is a much
more difficult problem, and one which
does not concern us here.
One point, however, these constella-
tions do tell US, and tell us plainly. They
show that the axis of the earth, which.
as the earth turns round the sun, moves
parallel with itself, yet, in the course
of ages, itself revolves so as in period
of some $4,000 years to trace out a circle
amongst the stars. This is the cause
of what Is called "precession, and ex-
plains how 1t Is that the star we call
the Pole Star today was not always the
Pole star, nor will always remain so.
We learn this fact from the circumstance
that the old consultations do not cover
the entire celestial sphere. They leave
great circular space of 40 degrees ra-
dius unmapped In the southern heavens.
This simply means that the originators