Mist, phosphorescent, 142.

Mitchell, protracted earthquake shocks in North America, 211.

Mitscherlich on the chemical origin of iron glance in volcanic masses, 234; chemical combinations, a means of throwing a clear light on geognosy, 256; on gypsum, as a uniaxal crystal, 259; experiments on the simultaneously opposite actions of heat on crystalline bodies, 259; formation of crystals of mica, 260; on artificial mineral products, 268, 271.

Mofettes (exhalations of carbonic acid gas), 215-219.

Monsoons (Indian), 316, 317.

Monticelli on the current of hydrochloric acid from the crater of Vesuvius, 235; crystals of mica found in the lava of Vesuvius, 260.

Moon, the, its relative magnitude, 96; density, 96; distance from the earth, 97; its libration, 98, 163; its light compared with that of the Aurora, 201, 202; volcanic action in, 228.

Moons or satellites, their diameter, distances, rotation, etc., 95-99.

Morgan, John H. "on the Aurora Borealis of Oct. 24, 1847." See Translator's notes, 194, 199.

Morton, Samuel George, his magnificent work on the American Races, 362.