This map, prepared by Prof. R. S. Dugan of Princeton University, shows the constellations as far south as the Southern Cross and is adjustable for the time of night, date, and for the latitude. Full instructions are given for its use. It is used in many schools and colleges. It is sold by the Camp Fire Stores Co., price 19 cents.
DEFINITIONS OF SOME WORDS AND
TERMS USED IN THIS BOOK
Action. The way in which a thing works.
Affect. To act upon; to change; to be moved or influenced by.
Almanac. A pamphlet or book containing tables showing the days of the year; also the time the Sun and Moon rise and set; the conjunctions, eclipses and other information concerning the things in the sky. The word almanac is supposed to be derived from the Arabic article al and the verb manac, which means to count.
Angular measurements. [See Appendix B].
Aphelion. The point where a planet or a comet is farthest away from the sun.
Apparent. To seem real. The daily motion of the Sun round the Earth is only apparent, for we know it is the Earth which turns round on its axis instead.
Arc. [See Appendix B].
Arc of circle. [See Appendix B].