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from the erroneous impression conveyed by the eye,that the stars have a sensible disk or magnitude; andto have such an apparent magnitude, if as distant asCopernicus would make them, Tycho calculated thattheir real size must be larger than the whole orbit ofthe earth. The answer is, we cannot say that thisis not the case. But again, the use of the telescope hassince shown that the assumption is incorrect, the starshaving no real disks.

The theological objections which appeared to Tychoso formidable against admitting the motion of the earth,were deduced from certain passages in scripture, in whichexpressions occur attributing motion to the sun and restto the earth. Considering the state of knowledge in histime, it is not a matter of surprise that such objectionsshould have possessed considerable weight. On the onehand, it must be remembered, that the question of thecelestial motions had not yet obtained any demonstrativesolution : and, on the other, though the light of the Re-formation had, before this period, been diffused throughoutEurope , yet the general illumination of the age was notsuch as to allow of accurate discrimination in the use orapplication of the sacred writings. The philosophicaltheory could not command absolute conviction ; and theuse thus made of the authority of scripture was notperceived to be a misapplication. Hence it cannot sur-prise us, that the two appearing to be at variance, theformer was maderto give way. In truth, it can hardlybe said, that even at the present day such questions areplaced upon their right basis. The advance of illumin-ation during several centuries, has hardly yet (amongthe generality of mankind) exhibited in their just lightsuch contradictions between the letter of scripture andthe results of science. But of this we shall see moreinstructive examples in the sequel. To return now toTycho. Fully impressed, in his own mind, with theweightof these objections, he directed his thoughts to framinganother system, by which they should be avoided. Hesupposed the five planets to revolve round the sun,