Letters on Astronomy

This edition has images. Title: Letters on Astronomyin which the Elements of the Science are Familiarly Explained in Connection with Biographical Sketches of the Most Eminent Astronomers Contents: Preface -- Introductory observations -- Doctrine of the sphere -- Astronomical instruments; telescope -- Observatories -- Time and the calendar -- Figure of the earth -- Diurnal revolution -- Parallax and refraction -- The sun -- Annual revolution; seasons -- Laws of motion -- Terrestrial gravity...