Pyritous ore, Mode of treatment of, 80 Q Quartz veins, Rosales’s igneous theory of, 34; objections thereto, 35, 36 R Rainfall, 178 Reef. See _Lodes_ Retort for small quantities of amalgam, 142; and of mercury, 143 Reverberatory furnaces, 101 _et seq._ Right angle, 158 Rivers, To measure width of, 157, 158 Robbery in gold-mills, Mode of preventing, 124-126 Ropes, Durability of, 173; Qualities of, 190 Rope-splicing, 166 Rosales on origin of quartz veins, 32-34 Rotomahana district, White and Pink Terraces in, 36 Rust, Solvent for, 165; Protecting iron and steel from, 165 Rutile, 32, 33 S School of Mines, S. Australian, 118 Screens, 78, 79 Shaft, Size of, 19, 27; Logging up, 27, 28; Depth of, 162; Connection of, with underground workings, 176; Data connected with, 177 Sheet-iron, Thickness and weight of, 189, 190 Shutes, Explanation of, 43 Signs, 185 Silica terraces in the Rotomahana district, 36 Silver ores, 31, 32 Silvering copper plates, 149 Skey, experiments on formation of sulphides, 39, 40; and on their properties, 41 Sluice plates, 156 Smelting, Rough, 141 Soap, Serviceable, 138 Specific gravity, 181, 182 Square roots, 191 Squares, 191 Stamp mills, 76, 78; Power for, 147 Steel, How to prevent rust in, 165 Stetefeldt shaft furnace, 106 Stream tin, 32 Sulphide of gold, Formation of, 39, 40, 45, 46 Sulphides, Experiments on properties of, 41, 42, 53; calcination of, 100 _et seq._ T Tank, to find contents of, 189 Telegraphic code, 138 Tent, 128-130 Thames gold-field, Siliceous sinter in, 36 Thermometer scales, Table of, 184 Thwaite-Denny furnace, 105, 106 Thwaite power gas system, 110 Thwaites’ furnace, 102 Timber, Data as to, 174 Tin, Minerals mistaken for, 32; How to distinguish them from, 33 Tin-mines at Mount Bischoff, 24 Tin ores, 32 Tree, To measure height of, 160 Tulloch ore feeder, 74, 75 V Vein, to find lost part of, 167 Velocity of falling fluids, 188 W Wages, Table for calculating, 192 Washing table, 79 Water, Purifying, 132, 133; Roots as a source of, 134, 135; Filtering of, 135; Mode of supplying, to stamper boxes, 146; Plan for raising, 163; Data regarding, 171; Fresh and Salt, compared, 188; Pressure of, 189 Water bag, 136 Waterless power, 109-112 Watson & Denny pan, 90 Weight of materials, 180 Weights and measures, 186, 187 Welcome nugget, 54, 55 Welcome Stranger nugget, 54 Wilkinson, on deposition of gold in iron pyrites, 51, 52 Windlass, 153 Wolfram, 32, 33 Woodside nuggets, 57 Printed by Ballantyne, Hanson & Co. Edinburgh & London * * * * * A SELECTION FROM