CHAPTER IV.

RELATIONS OF THE SEPARATE ORBS OF OUR GALAXY. THE DOUBLE STARS.-MULTIPLE SYSTEMS.

IT

is not possible to reflect long on the wonderful objects that have passed under our review, without the question occurring-What is the internal condition of a galaxy or cluster? Are the orbs composing it motionless? Do they preserve for ever their existing relationship; and, as a consequence of this immobility, are the forms we descry, as they always have beenand alone can be-rigid and changeless? If such inquiries are capable of being pursued with success, it is evident that we shall obtain our first information among the bodies nearest us, I mean among the stars of our own galaxy: and fortunately there is here no longer dubiety or darkness, for we are to follow a course of discovery which might be the distinction of any epoch, and that constitutes one of the proudest titles of ours to be for ever illustrious in astronomy.

L

I.

There had been observed, at least since the time of GALILEO, a small class of stars, in which individual orbs are found unusually near each other. The more remarkable of these bodies are so close, that they cannot be separated by the naked eye, but appear as single stars, until analyzed and divided by good telescopes. For the most part they are exceedingly beautiful; and some idea of their variety in sizes and relative distances may be obtained from Plate XVIII. where the following eleven are supposed to be seen through the same telescope.

* The figures are supposed to begin at the top of the Plate, and

to move from the left hand to the right.