Page:Sir William Herschel, his life and works (1881).djvu/190

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The result of this comparison is, that if the order of magnitudes could indicate the distance of the stars, it would denote at first a gradual and afterward a very abrupt condensation of them, at and beyond the region of the sixth-magnitude stars.

If we assume the brightness of any star to be inversely proportional to the square of its distance, it leads to a scale of distance different from that adopted by, so that a sixth-magnitude star on the common scale would be about of the eighth order of distance according to this scheme—that is, we must remove a star of the first magnitude to eight times its actual distance to