It is far from the least singular of these recent G-star outlet revelations of Lord Rosse, that, attached even to the simplest and most regular shapes of the external clusters, are stray filaments, dim and sparse, groping outwards, as it were, from the mass of the system, into surrounding vacancy; are those such arms attached laterally to the principal regions of our galaxy, or are they portions of its general structure, piercing into vacuities yet more wild and perilous, and carrying its relations onwards towards the sphere of other systems ? Whatever their character or function, all hope of giving form or definite outline to the Milky Way, now necessarily disappears; we are dealing with magnitudes so vast, so transcending comparison witlt any palpable unit, that they merge into what is formless.III. Proper Motions Of Tiik Stars.— Under Sun, the circumstances have been alluded to that led to the definite discovery of the grand motion of translation of our luminary. Not only is it most improbable, that, alone of all the stars, our sun moves in some gigantic orbit: but the discovery of the G star jeans latter fact, involved the discovery of proper motions in the stars also. The reality and direction of the Sun's path, is established by the circumstance, G star raw Uiat the stars en masse seem drifting'in a certain direction,—that is to gay, the sum of their apparent motions is of this nature; and that sum is so clear, that no doubt remains as to its reality. Hut eiri single star does not drift in this way. On the contrary, taking them individually, they seem to move very G-star irregularly; and the irregularity establishes and expresses the existence of projitr motions for each star. To detect the amount G star of their proper motions, the effect of the Sun's motion must eliminated from the apparent changes of place discerned in each star ; the residue is the quantity we desire.
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