Page:Popular Science Monthly Volume 47.djvu/522

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THE POPULAR SCIENCE MONTHLY.

the real motive for scientific research all such danger is dissipated, and he will earnestly seek to add his life work as—


" . . . a closer link
Betwixt us and the crowning race

"Of these that eye to eye shall look
On knowledge; under whose command
Is Earth and Earth's, and in their hand
Is Nature like an open book;

"No longer half akin to brute,
For all we thought and loved and did,
And hoped, and suffered is but seed
Of what in them is flower and fruit.

PLEASURES OF THE TELESCOPE.

By GARRETT P. SERVISS.

VI.—FROM LYRA TO ERIDANUS.

WE resume our celestial explorations with the little constellation Lyra, whose chief star, Vega (α), has a very good claim to be regarded as the most beautiful in the sky. The position of this remarkable star is indicated in map No. 17. Every eye not insensitive to delicate shades of color perceives at once that Vega is not white, but blue-white. When the telescope is turned upon the star the color brightens splendidly. Indeed, some glasses decidedly exaggerate the blueness of Vega, but the effect is so beautiful that one can easily forgive the optical imperfection which produces it. With our four-inch we look for the well-known companion of Vega, a tenth-magnitude star, also of a blue color deeper than the hue of its great neighbor. The distance is 50″, p. 158°. Under the most favorable circumstances it might be glimpsed with the three-inch, but, upon the whole, I should regard it as too severe a test for so small an aperture.

Vega is one of those stars which evidently are not only enormously larger than the sun (one estimate makes the ratio in this case nine hundred to one), but whose physical condition, as far as the spectroscope reveals it, is very different from that of our ruling orb. Like Sirius, Vega displays the lines of hydrogen most conspicuously, and it is probably a much hotter as well as a much more voluminous body than the sun.

Close by, toward the east, two fourth-magnitude stars form a little triangle with Vega. Both are interesting objects for the telescope, and the northern one, ε, has few rivals in this respect. Let us first look at it with an opera glass. The slight magnifying