Page:Reflections upon ancient and modern learning (IA b3032449x).pdf/125

 or mentioned in the Writings of the Ancient Philosophers and Historians. By which Deduction, the former Number will be yet again considerably lessened.

Now, a very true Judgment of Ancient Skill in Natural History may be formed out of Pliny, whose Extracts of Books, still extant, are so particular for the present Purpose, that there is Reason to believe they were not made carelesly of those that are lost. Galen seems to have read whatever he could meet with relating to Medicine, in all its Parts: And the Opinions of Abundance of Authors, whose Names are no where else preserved, may be discovered out of his Books; of the famous ones especially; whom at every Turn he either contradicts, or produces to fortifie his own Assertions. Ptolemee gives an Account of the old Astronomy in his Almagest. Very many Particulars of the Inventions and Methods of Ancient Geometers are to be found in the Mathematical Collections of Pappus. The Opinions of the different Sects of Philosophers are well enough preserved in the entire Treatises of the several Philosophers who were of their Sects; or in the Discourses of others, who occasionally or expresly confute what they say. So that I am apt to think, that the Philosophical and Mathe-