Part 39

Umbra, 11, 12, 19, 20.

United States, comparison, 24.

Uranus, 3, 196.

Vapor, 28.

Vega, 235, 246.

Vegetables, 74.

Veils, 14, 17.

Venus, 118.

Vernier, 3.

Vesuvius: crater, 155, 157; eruption, 181, 183. (See Naples.)

Vibrations, 72.

Victoria, 115.

Viscous Fluid, 26.

Vital Force, 14.

Vogel, H. C., 64, 66.

Voids, 181, 227.

Volcanoes, 27, 28; in moon, 167, 193.

Wandering Star, 101. (See Comets, Falling.)

Washington: Observatory, 2, 86–88; telescope, 122; Monument, 182.

Water, 152; in man, 221.

Waterloo, 80.

Water-wheel, 111.

Watson’s Observations, 49.

Wheat, prices, 79. (See Breadstuffs, Corn, Grain, Sun-spots.)

Wheel, comparison, 10.

Whirlpools, 28, 31.

Whirlwinds, 23, 31.

White Light (q. v.), 48, 62, 63.