ABSTRACT
Astronomy was a positive science, in its geometrical aspect, from the earliest days of the School of Alexandria; but physics, which we are now to consider, had no positive character at all till Galileo made his great discoveries on the fall of heavy bodies. The distinction between physics and chemistry is much less easy to establish, and it is one more difficult to pronounce upon from day to day, as new discoveries bring to light closer relations between them. The general properties of physics were, in the metaphysical days of the science, regarded as consisting of two classes: those that were necessarily, and those that were contingently, universal. Observation was, in astronomy, restricted to the use of a single sense; but in physics, all our senses find occupation. The next great virtue of physics is its allowing the application of mathematical analysis, which enters into this science, and at present goes no further—not yet, with real efficacy, into chemistry.
