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192 placed at a distance so small as 19,200,000,000,000 miles from the sun; but certain most admirable observations and measurings, made by the illustrious Bessel, have since clearly established the astounding fact that the fixed stars placed nearest to our solar system are distant from it some 57,000,000,000,000 miles—a distance utterly inconceivable by the human mind. Light travelling, as is well known, at the rate of 192,000 miles per second, it will take a ray from the fixed stars nearest to us some $9 1⁄3$ years to reach the earth! But if this nearest and comparatively trifling distance is sufficient to appal the human understanding, what shall we say or think of the immeasurably greater distances which separate us from the remoter stars, and from the most distant visible nebulæ, whose light, it has been calculated, will take at least a million years to reach our earth! To arrive at some approximate estimation of the real magnitude of the stars, the light which they shed on us, and the most imperfect and as yet still almost entirely negative knowledge which we have obtained respecting their distances, must be our only guide. Now, direct photometrical experiments have shown that the light of Sirius, the most brilliant of the fixed stars, is, at equal distances, $146 1⁄2$ times more intense than that of our Sun, and that it would accordingly require a collection of more than 146 suns to shed a ray of light on our earth