Excerpt from Philosophiæ Naturalis Principia Mathematica Nec latet extremos quee vis circumrotat orbes. Sol solio residens ad se jubet omnia prono Tendere descensu, nec recto tramite currus Sidereos patitur vastum per inane moveri. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.