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Rh thankful. The plan as well as the labour of thus estimating "the contents of the heavens," and lifting man's mind to a higher level than it ever attained before, were altogether his own, unless we add that his devoted sister Caroline shared the labour and, it must be added, the dangers of the work. What a vista of eternity and infinitude was unfolded by the musician of Bath! It seemed as if he had built a bridge for thought to span the gulf which separates the finite from the infinite, the temporal from the eternal, in this incredible profusion of suns and systems, of inconceivable spaces and times.

Of the length, breadth, and thickness of these strata of millions of stars that form the Milky Way, we have but the faintest conception. Still, Herschel made an estimate, which shows the immensity of space covered by this island of stars in the ocean of infinitude, if we may still presume to speak of it in these terms. "In the sides of the stratum opposite to our situation in it, where the gauges often run below 5, our nebula"—the white cloud called the Milky Way—"cannot extend to 100 times the distance of Sirius." But we know now, what Herschel did not know, that light, which darts from the sun to our earth in eight minutes, takes about ten years at the same rate to travel the distance between Sirius and us. One hundred times that distance would be traversed by light in 1000 years. And, if the farthest-off stars of the Milky Way are nearly five hundred times as far away from our earth as Sirius, the swift messenger who brings us tidings of them would be five thousand years on his journey, and could only tell us what was then taking place, opt what may be happening now. Herschel