Division of methods of treating ores--Scientific extraction indispensable--Superficial knowledge--German and Australian methods compared--Schools of Mines--Antiquity of gold working--Miner’s equipment--Tub, cradle, long tom--How operated--Hydraulic mining--Extensive Australian drifts--Extraction of reef gold--Amalgamation--Crushing appliances--Preference for stampers--The Lemichel syphon--The Griffin mill--The Huntingdon mill--Dodge crusher--Krupp Grusonwerk Ball Mill--Premature plant erecting--Danger of untried processes--Double faulted lode--Automatic ore feeders--Machinery site--Foundations for battery--Weight of stamps--Power and water required for battery--Selection of screen--Fall of tables--Ancient Egyptian gold washing table--Blanket tables--Successful treatment of refractory ore in Australia--Methods vary with ore--Importance of even crushing--Points _re_ crushing--Best form of stamper box--Cleaning plates--Form of scraper--Retorting amalgam--Special difficulties, how to overcome them pp. 59-86 CHAPTER VII GOLD EXTRACTION (SECONDARY PROCESSES AND LIXIVIATION) Choosing the plant---Various ores and their constituents--Amalgamation--Various concentrators--Percussion tables--Frue vanner--Pan concentration--Simultaneous grinding and amalgamating condemned--Watson and Denny pan--Good machines often condemned--Procedure in ore treatment--Duncan pan--Calcining--Rotatory amalgamator--Steaming concentrates--Dry amalgamation--Sulphuric acid and sickened mercury--Amalgamation without overflow--Experiments--Steam as an agent in gold extraction--Lixiviation by chlorine--Various processes--Mount Morgan--Cyanide process pp. 87-99 CHAPTER VIII CALCINATION OR “ROASTING” OF ORES Effect of roasting--Various methods--Reverberatory furnaces--Howell, White, Brückner, Thwaite-Denny, and Molesworth types of revolving cylinder furnaces--Shaft type--The Stetefeldt furnace--Chimneys--Depositing chambers pp. 100-108 CHAPTER IX MOTOR POWER AND ITS TRANSMISSION Water and steam power--Waterless power plant described--Oil engines--Electric transmission--Advantages of electric power--Its possibilities pp. 109-112 CHAPTER X COMPANY FORMATION AND OPERATIONS