NEBULAE. 



181 



of wild fowl, discovered by Kirch in 1681, is on the shield which Hevelius framed among 

 the stars in honour of John Sobieski, the deliverer of Vienna from the Turks. 



Nebula in 30 Doradus. 



In Pollux. 



And in Sobieski's Shield. 



The conclusions are marvellous that are forced upon us by these objects. Here we 

 have firmaments or clusters, insulated in space, each constituting a sidereal family equal 

 to that to which our sun belongs. " It would be a vain task," says the highest authority 

 upon this subject, " to attempt to count the stars in one of these globular clusters. They 

 are not to be reckoned by hundreds ; and on a rough calculation, grounded on the ap- 

 parent intervals between them at the borders (where they are seen not projected on each 

 other), and the angular diameter of the whole group, it would appear that many clusters 

 of this description must contain, at least, ten or twenty thousand stars, compacted and 

 wedged together in a round space, whose angular diameter does not exceed eight or 

 ten minutes ; that is to say, in an area not more than a tenth part of that covered by 

 the moon. Perhaps it may be thought to savour of the gigantesque to look upon the 

 individuals of such a group of stars like our own, and their mutual distances, as equal to 

 those which separate our sun from the nearest fixed star : yet when we consider that 

 their united lustre affects the eye with a less impression of light than a star of the fifth 

 or sixth magnitude, (for the largest of these clusters is barely visible to the naked eye,) 

 the idea we are thus compelled to form of their distance from us may render even such 

 an estimate of their dimensions familiar to our imagination ; at all events, we can hardly 

 look upon a group thus insulated, in seipso totus, teres, atque rotundus, as not forming 

 a system of a peculiar and definite character." 



However it may savour of the gigantesque, it is sufficiently evidenced that an area 

 of the heavens not exceeding -^ of the lunar diameter, contains a system of stars 

 rivalling in number those which constitute our firmament, and appearing only as a 

 single faint luminosity to us. Yet there are many areas so occupied. It follows 

 therefore that our firmament is but one of a series, and probably one of the smaller 

 chambers in the great mansion of the universe* All the stars and constellations that shine 

 in the midnight sky, constitute a stellar scheme which is but a unit of a countless number. 

 As seen from the faint objects we discern in the side of Hercules and the sword a hahdle 

 of Perseus, our whole sphere would be compressed into a. small streak of light, and 

 appear in space like a snow flake in our atmosphere! We may conclude, however, that 

 as the firmament, which the unaided eye of man surveys, is but a member of a vast 

 family of systems which his assisted vision scans, so that family may be no more than 

 as a drop to the ocean, a grain of sand to the mass of the globe, compared with what 

 lies beyond the bounds of telescopic sight, hid in regions which mortal gaze will never 

 explore or visit. Suppose we could actually travel across the space through which the 

 terrestrial eye can penetrate, and take our station at the point which is now the limit of 

 vision, would there not be a territory lying before us, equal to that we should have left 

 behind, in the number, grandeur, and variety of its works ? That the Divine capability 



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