supposition, in his ring-system and family of satellites. It is very well to grow rapturous, as many besides Brewster and Chalmers have done, over the beauty of the Saturnian skies, illuminated by so many satellites and by the glorious rings; and it is very proper, no doubt, for those who so view Saturn's system, to dwell admiringly on the beneficence with which all this abundance of reflected light has been provided, to make up to the Saturnians for the small amount of light and heat which they receive from the sun. But, unfortunately for this way of viewing the matter, the satellites and rings do not by any means subserve the purposes thus ascribed to them. Even if all the satellites could be full together, they would not supply a sixteenth part of the light which we receive from our full moon; and they cannot even appear very beautiful when we consider that the apparent brightness of their surface can be but about one-ninetieth of the brightness of our moon's. As for the rings, so far from appearing to be contrived specially for the advantage of Saturnian beings, these rings, if Saturn were inhabited, would be the most mischievous and inconvenient appendages possible. They would give light during the summer nights, indeed, when light was little wanted, though even this service would be counteracted by the circumstance that at midnight the enormous shadow of the planet would hide the greater part of the rings. But it is in winter that the rings would act most inconveniently; for then, just at the season when the Saturnians would most require an additional supply of light and heat, the rings would cut off for extensive regions on Saturn the whole of the solar light and heat which would otherwise be received. Dr. Lardner was quite mistaken in supposing (after a cursory examination of the mathematical relations involved) that the eclipses so produced would be but partial. His object was excellent, since he sought to show that "the infinite skill of the Great Architect of the universe has not permitted that the stupendous annular appendage, the uses of which still remain undiscovered, should be the cause of such darkness and desolation to the inhabitants of the planet, and such an aggravation of the rigors of their fifteen years' winter," as would result from eclipses lasting many months or even years in succession. But we must not endeavor to strengthen faith in the wisdom of the Almighty by means of false mathematics. So soon as the subject is rigorously treated, we find that Sir John Herschel was quite right in his original statements on this subject. The present writer published, in 1865, a tabular statement of the length of time during which (according to rigid mathematical calculations) the eclipses produced by the rings last in different Saturnian latitudes. The following quotation from the work in which this table appeared will serve to show that the partial daily eclipses conceived by Lardner are very far from the truth, or rather are only a part, and a very small part, of the truth: "In latitude 40° (north or south), the eclipses begin when nearly three
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