INDEX. 273 
Marl, description and uses of, 114 
Matrix, 4 
Meerschaum, how obtained, prepared, and used, 84 
Mercury, the ores of, 173 
mines in India, description of, 175 
, how extracted from the ore, 175 
, properties and uses of ; 175, 176 
Metals, different states in which they are found, 165 
, how obtained and prepared for use, 165. 
Meteoric stones, description of, 193 
. , extraordinary instances of their falling from the 
air in 1492, 1672, 1704, 1795, 1814, &c. 195 
, opinions of learned men respecting, 197 
, properties of, 194 
Mica, description of, how obtained, and uses of, 81 
Mica slate, or micaceous schistus, 227 
Millstones. See Burr Stone. 
, Peak, what formed of, 233 
of granite, 225 
Millstone grit, description and uses of, 233 
Mineral green, of what made, 141 
Mineral oil. See Petroleum. 
Minerals, systematic arrangement of, 4 
Mineral tar, description and uses of, 148, 149 
Minium, how manufactured, and uses of, 206 
Mochoa stone, description and use of, 63 
, imitations of, how made, 63 
Mona marble. See Serpentine. 
Moonstone, description and use of, 70 
Mountains, comparative heights of the principal, 237 
Muriatic acid, 13 
Muriats, 13 
Muscovy glass. See Mica. 
Music plates, of what made, 217 
N. 
Naphtha, where found, uses and properties of, 146 
Natron, description of, how obtained and uses of, 128 
Nephrite. See Jade. 
Nickel, description and uses of, 208 
, oxide of, and for what used, 209 
Nitrats, 14 
Nitrat of silver, uses of, 181 
Nitre, description of, how and whence obtained, 136 
, how manufactured, and uses of, 136,137 
Nitric acid. See Aqua fortis. 
Nova Mina topaz, 37 
