The National Observatory [pp. 304-308]

1849.] The National Observatory. 305
Catalogue, was to penetrate regularly and systematically with some one of our powerful telescopes, every point of space in the visible heavens, for the purpose not only of determining accurately the position of every star, cluster, and
nebula, that the instruments can reach, but for
the purpose also of recording magnitude and
color, with angle of position and distance of binary stars, and of making drawings and giving
descriptions of all clusters and nebulae. And for
this, arrangements were commenced in 1845.
Now it may be asked, why make this work so
extensive? Why comprehend in it objects that
never have been, and never can be seen by the
naked eye?
The answer is ready with reasons abundant.
The heavens like the earth, are obedient to the
great law of change. The stars are undergoing
perpetual change, some change their position,
betrays his trust, and thereby wrongs the living
and defrauds posterity.
In 1795, Lalande saw a star, and entered it
upon his catalogue. In 1847 it was discovered
at the Washington Observatory that that star
was the planet Neptune. Thus, by the fidelity
of that observer, and the means of his catalogue,
we are enabled to know at once what otherwise
we should have had to wait fifty years to learn.
But for that observation of Lalande, astronomers would have had to watt half a century for
data to enable them to determine the orbit of that
planet as accurately as Mr. Walker, formerly an
assistant at the National Observatory, has done
in consequence of the discovery there.
Perhaps the most exquisitely beautiful objects
in the heavens, are the double stars, with their
contrast of colors. When the telescope is turned
upon these objects, the most richly-colored orange
some vary in magnitude, some in color, and some star may be seen dancing along with its comhave blazed forth like flaming meteors in the sky, panion of bright green, or smalt blue. They
dazzled the world, and then disappeared for- are arranged in pairs or groups, with their comever. ponents diversified with almost all the colors of
The appearance of a new star in the firma- the rainbow.
ment induced Hipparchus before the Christian It was a long time a question whether these
era to undertake the first catalogue, which al- stars were really double, or only optically so. It
though lost to the world was productive of great was thought they appeared double, only because
practical good. Ptolemy is said to have borrow- they happened to be situated nearly in the same
ed over freely from it. direction; that one was placed at an infinite dis In November, 1572, a star appeared all at once tance bayond the other. It was said, therefore,
in great splendor. It surpassed Sirius in bril- that they appeared optically near each other only,
liancy, and was brighter than Jupiter in perigee. like lamps afar off in a dark night, which, though
It could be seen in the day time, with the naked at a great distance apart, appear close together
eye, and after two years it passed away and dis- to one who sees them nearly in the same straight
appeared. Its place in the sky is now vacant. line.
It induced Tycho Brahe to undertake his cata- These stars are so remote from us, that a snail
logue. might travel at his usual gait many times around
It may be that there is now, at this very time the earth,.before that type of velocity with us, a
in the firmament above, a world on fire.,Argus, cannon ball, could reach the nearest of them.
a well-known star in the Southern hemisphere, How then could it be ascertained whether they
has suddenly blazed forth, and from a star of the were physically double, or only optically so?
2nd or 3rd magnitude, now glares with the bril- Catalogues and the resources of science have
liancy of the first. enabled astronomers to settle the question.
It is man's boast that he was made to look If while looking at the leaves on the trees of
aloft; for his alone is the privilege to pry into a forest, I hold up a dime at a certain distance
"Nature's infinite book of secresy," and can it before me, I will see that it hides certain leaves.
be therefore profitless to him and of no value to If now I hold a dollar at the same place, I will
posterity to survhy the skies, map the stars and find that the additional leaves hid by it,; will excontemplate "the eternal flowers of heaven?" ceed, many times in number the first, because
The generation that succeeds is always wiser the leaves are situated one beyond the other.
that that which precedes; for this begins with They are optically close together; and the addiknowledge, advancement, and discovery where tional space optically hid by the dollar is much
that left off. Our ancestors gathered facts, and larger than that hid only by the dime.
recorded observations, which in our hands have Now apply this test to the double stars. Take
become clues guiding to knowledge, or leading the space in the heavens about each star, that
to discovery. Shall we do less? He who has would be hid by a pin's head when held at a
the privilege of interrogating nature in the name convenient distance for vision, and count the
of society, and yet fails to preserve her answers, stars that would be included within the space so
is regarded by the scientific world as one who hid. Now hold a half dime at the same distance
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