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3. A crushing battery having forty stamps of 1,000 lb. each makes ninety-seven blows per minute, and has a drop of 7 in. at each blow : show by calculation the force exerted in foot pounds. 4. The head and shoe of a stamp is 21 in. long, and 9 in. in diameter, of cast-iron, and the stem is of wrought-iron, 14ft. long, 3|in. in diameter: show by calculation the weight in pounds of the head, shoes, and stem. 5. Describe a Huntington mill of 5 ft. diameter, and give a detail of the different parts and appliances required to be fixed in conjunction with this mill as an ore-pulveriser. 6. Describe and also show by sketch a mortar-box suitable for dry-crushing, and the automatic appliances used to convey the pulverised ore into a bin. 7. If gold were very finely disseminated through the ore, what mesh of screens would you use for dry-crushing? and give your reasons fully. 8. What are the advantages or disadvantages of using stamps for pulverising the ore when it has to be treated with cyanide solutions ? Subject B. — Amalgamating-machines. 1. Show by sketch an amalgam-trap, and describe how it is placed and applied. 2. Give the speed that Wheeler's, McKay's, and combination-pans require to be worked, and horse-power required to work them, and quantity of material they are capable of operating on in twenty-four hours. 3. What is the difference between a Watson-Denny pan and a combination-pan ? Describe fully. 4. Show by sketch a berdan, and describe its action, the quantity of quicksilver you would use in it, the speed and angle at which it is set, and give the horse-power required to work it. 5. Describe the King amalgamator, and its action, giving its speed, and all details. 6. What are settlers used for ? Give their dimensions, and describe fully how they work.

First Day.—Time : 2 p.m. to 5 p.m. Subject C. — The Use of Quicksilver and the Methods of using it in connection with the Extraction of Gold and Silver from Ores. 1. Describe how you would clean copper plates and coat them with quicksilver; also how you would remove gold amalgam. 2. What is the chemical effect of using chloride of sodium and sulphate of copper in panamalgamation ? What are the advantages or disadvantages in using these salts ? 3. What effect has an electrical action on quicksilver used for amalgamating purposes, and how is it applied ? 4. What class of auriferous and argentiferous ores are best suited for the recovery of the gold and silver by amalgamation ? 5. What effect have ores containing sulphides of zinc and antimony on quicksilver used for amalgamation of the gold and silver the ore contains ? 6. Describe how you would separate the gold and silver from quicksilver when in the form of amalgam ; also how you would purify quicksilver charged with base metals. Subject E. — Chlorination Process of Recovering Gold from Ores. 1. What class of ore is best suited for chlorination? State fully, giving your reasons why. 2. Describe a modern chlorination plant, giving all details, and show the advantages it has over the Plattner chlorination process, giving the time and quantity of material operated on in each charge. 3. Describe the different methods by which chlorine gas is generated, giving the composition of chemicals used, and also state how it is applied to the ore. 4. State the different processes used for precipitating the gold from chlorine solutions, giving full details. 5. How would you recover any silver that was in ores treated by chlorination ? Describe the process you would use fully. 6. Show by sketch a modern chlorination plant, with all appliances, with distinguishing letters on each part. 7. Describe how you would roast ore in a reverberatory furnace. Give full details of the process, and state what chemicals you would use (if any), and give the reason why, and the-action that the chemicals used produce on the ore. 8. Describe how ores are roasted in the Bruckner, White-Howell, and Stedtefelt furnaces, and give the action of each.

Second Day.—Time : 9 a.m. to 1 p.m. Subject D. — Lixiviation Process of Recovering Gold and Silver from Ores. 1. Show by sketch a cyanide plant with five percolating-vats for treating auriferous and argentiferous ores, and give full details as to the dimensions of each part, and how it is placed. 2. Describe the whole process of treating ores with cyanide solutions, and how you would prepare a strong solution, and the method of dissolving the salt. 3. How would you ascertain the strength of a cyanide solution ? Describe fully. 4. State how gold and silver are precipitated from cyanide solutions, and the different methods adopted, giving full details. 5. State how you arrive at the strength of the cyanide solutions best suited to the class of ore you have to deal with.