To these difficulties I add some more. One … [initial] plane to be horizontal, which would be neither rising nor … at the same distance from the center, which … [Salviati] All the difficulties and objections you advance … grant them all, as I believe our Author … the concrete … These liberties are pardoned to him by some … comparison with the great distance to the center … as if it were a straight line, and … [Archimedes makes similar assumptions in his books].
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