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the feed-heater into the boilers. The big lift-pump raises the clear water to the height of the second stage (for middle-sized grainings) to the reservoir. From out of this a second pump lifts the necessary water to the upper and top storey. The necessary water for working the tables is taken from the principal reservoir below. The water, which is clarified in the settling-tanks—that is, water that has already been used —flows back into the shaft of the pump and is recirculated. Two hundred and nine gallons of water are discharged from the tanks per minute." The following notes on the Liihrig concentrating system, by W. C. Chapman, are taken from the Victorian Mining Beport:— "Notes on the Luhrig Concentration System. " The Liihrig Company, in the first place, requires the following questions answered, and a sample of ore weighing not less than two tons sent for testing and examination :— " Questions. " 1. How does ore occur at .your mines ? " 2. How much of your ore can you sell without previous treatment? " 3. Is the mineral impregnated finely, or is it in coarse crystals? " 4. Is the gold found in sulphides, and of what size are the crystals ? " 5. Is the gold found as free gold in quartz, and is it visible with the naked eye? " 6. How many tons of gangue can you raise per 10 hours ? "7. What percentage of total output must go to the dressing-plant? " 8. Is the rock hard, clayey, or earthy? "9. What are the costs of bringing one ton of the ore to the surface ; and what percentage of the above-named minerals does an average sample contain ? " 10. Have you a dressing plant at work ? "11. Of what is the plant composed ? " 12. Have you stone-breakers, stamps, mills, and Frue vanners at work? " 13. Do you use amalgamation ? " 14. What loss of gold in percentages, or how much gold, silver, &c, are you unable to win ? " 15. How small do you crush your ore, with stone-breakers, stamps, &c. ? " 16. What size, in inches, of ore do you feed into the breakers, stamps, &c. ? " 17. How much water does your plant use per minute ? " 18. What are your costs of working per ton of ore ? " 19. Do you employ steam-power, and what horse-power ? " 20. Or do you employ water-power, water-wheels, or turbines, and of what size are they ? " 21. If you use water-power, how many cubic feet of water have you, and what fall in feet ? " 22. What wages do you pay to labourers, smiths, mechanics, carpenters, and foremen, per day? " 23. What is the price of coal per ton delivered at the works? " General Bemarks. " If your dressing plant consists of stone-breakers, stamps, Frue vanners, &c, and if you use the amalgamation process you are employing the most expensive and incomplete process in existence. With my patented system I win all the particles of the mineral, intergrown with quartz, which are not caught by the quicksilver. It is very expensive to crush these particles again, after having passed the quicksilver in stamps and mills. Slimes w-hich generally go to waste, or are stored up in settling-pits, are collected by an automatic and continuous filter in my system, and the slimes are raised for further working up. Moreover, I allow only practically clear water to go to waste. The whole of the machinery and apparatus are delivered by me, constructed on the most approved principles, of very best workmanship, and at low rates. I undertake the complete erection of a dressing plant, and give full guarantees respecting the quantity and quality of the ores to be treated, also the loss and the cost of working, on condition that I receive an average sample of the ore—say, one or two tons, or any such quantity as may give a good average sample for testing purposes. The erection of a plant of 150 tons capacity per ten hours would take four months. A plant of 300 tons capacity uses 15 cubic feet of water per minute; a 600-ton plant 20 cubic feet a minute. The water is reused, and the slimes are extracted automatically and continuously. In Europe I have erected 153 plants for various kinds of ores, and I hereby invite likely clients to use the same. "On returning this list of questions a plan of the site should accompany it. On this the position of the bins and site should be shown ; also railway-siding and docks, if any. You should also inform me of the means of transport, distance of the nearest railway-station from the site, also the class of ground the plant is to be built upon.—C. Luhrig, Mining and Ore-dressing Engineer, Dresden, Saxony. " After fully testing the ore an estimate is given for the cost of a plant (f.0.b., Germany), and a list is given of the numbers of the different appliances, together with the price of each. In the event of a plant being ordered, an agreement is entered into between the Luhrig Company and the mine-owners fixing the guarantees on the part of the Liihrig Company and the royalty to be paid by the mine-owners. The Luhrig appliances for ore-dressing are much the same as those used under any system —that is to say, stone-breakers, sizing-drums, rolls, jigs, stamps, elevators, pointed boxes, and slime-vanners; but the form and construction of these is more scientific and better than any other ; and the system upon which it is planned, together with the vanners, is Luhrig's own invention, and devised for giving the best results with the least amount of manual labour and of loss. The coal plants are to be seen all over Germany and France, and some are in operation in England. They are most successful. The ore-dressing plants are in use in many places in Germany, making ore pay that would yield no profit before. At Himmelfahrt, near Freiberg, they are concentrating 15—C. 3.