CHAPTER IV.

THE FORM, MAGNITUDE, WEIGHT, AND DENSITY OF THE LUNAR GLOBE. 31 Form of Moon—Not perfectly Spherical—Bulged towards Earth—Diameter—Angular Measure—Linear Measure—Parallax of Moon—Distance—Area of Lunar Sphere—Solid Contents—Mass of Moon—Law of Gravitation—Mass determined by Tides and other Means—Density—How obtained—Specific Gravity of Lunar Matter—Force of Gravity at Surface—How determined—Weights of similar Bodies on Earth and Moon—Effects of like Forces acting against Gravity on Earth and Moon