Transcriber’s Note Italic text displayed as: _italic_ POPULAR LESSONS IN ASTRONOMY, ON A NEW PLAN; IN WHICH SOME OF THE LEADING PRINCIPLES OF THE SCIENCE ARE ILLUSTRATED BY ACTUAL COMPARISONS, INDEPENDENT OF THE USE OF NUMBERS. BY FRANCIS J. GRUND, AUTHOR OF “AN ELEMENTARY TREATISE ON PLANE AND SOLID GEOMETRY,” “ELEMENTS OF NATURAL PHILOSOPHY AND CHEMISTRY,” &c. [Illustration: Decoration] BOSTON CARTER, HENDEE AND CO. 1833. ENTERED according to Act of Congress, in the year 1833, By FRANCIS J. GRUND, in the Clerk’s office of the District Court of Massachusetts. I. R. BUTTS, SCHOOL STREET. NOTICE. The Geographical Miles, which are used in the scales and tables of this book, are _German Geographical Miles_, of which 15 make one degree. The teacher or pupil may easily change them into _English Geographical_ Miles, by multiplying them by 4, the square miles by 16, and the cubic miles by 64. PREFACE. Although many elementary works on Astronomy are already before the public, yet it is believed there is none in which the various magnitudes, surfaces, and distances of the heavenly bodies, are presented to the eye of the learner by actual comparisons;—the only way, perhaps, in which young pupils can be expected to form a correct idea of them. This the author has attempted in the following pages. The comparative diameters, surfaces and distances of the different planets, are all drawn, in the plates, according to a fixed scale of geographical miles; the surfaces of the planets are actually reduced to square measure, and drawn in proportion to each other and the sun; so that the youngest pupil, by a mere glance of the eye, is enabled to form a correct idea of their respective magnitudes. A similar plan has been pursued, in regard to the division of the Earth into Zones, and with respect to the extent of the five great Continents of our Globe. The Appendix contains an exposition of the population of America, Europe, Asia, Africa, and Australia, accompanied by a plate for the illustration of the comparative settlements on those Continents. _Boston, June 24, 1833._ POPULAR LESSONS IN ASTRONOMY. LESSON I. THE EARTH IN ITS RELATION TO THE SUN, MOON AND STARS. § 1. The Earth on which we live, and on which plants, trees and animals successively live and die, is only a small part of the world; it is but one of the smallest bodies in the Universe. To the world belong yet the _Sun_ from which we receive warmth and light, the _Moon_, and an innumerable class of bodies, which, at night, appear to us as so many points of light. These are called _Stars_. The reason why the Stars appear to us so small, is because they are so far from us; and things appear smaller in proportion as they are farther removed from us. This you will have noticed, when looking from a high steeple on the people below, or on a vessel far out in the harbour, or on a chain of mountains at a great distance.