ABSTRACT
This chapter distinguishes three kinds of astronomy, each with a different origin and history, but all mutually dependent, and composing, in their fundamental unity, one science. First in order of time came the art of observing the returns and measuring the places of the heavenly bodies. The second kind of astronomy was founded by Newton. Its nature is best indicated by the term “gravitational;” but it is also called “theoretical astronomy.” The third and last division of celestial science may properly be termed “physical and descriptive astronomy.” The advance of astronomy in the eighteenth century ran in general an even and logical course. The age succeeding Newton’s had for its special task to demonstrate the universal validity, and trace the complex results of the law of gravitation. The rise of Herschel was the one conspicuous anomaly in the astronomical history of the eighteenth century.
