. The prospector's field-book and guide in the search for and the easy determination of ores and other useful minerals. For this purpose the mass of gold dustand iron sand is allowed to become perfectly dry,and small quantities of it at a time are placed in aninstrument called a blower—a sort of a shallowscoop, made of tin and open at one end. Holdingthe blower with its mouth pointed away from him,and gently shaking it so as constantly to change theposition of the particles, the operator blows gentlyalong the surface of the contents, regulating theforce and direction of his breath so as to rem
. The prospector's field-book and guide in the search for and the easy determination of ores and other useful minerals. For this purpose the mass of gold dustand iron sand is allowed to become perfectly dry,and small quantities of it at a time are placed in aninstrument called a blower—a sort of a shallowscoop, made of tin and open at one end. Holdingthe blower with its mouth pointed away from him,and gently shaking it so as constantly to change theposition of the particles, the operator blows gentlyalong the surface of the contents, regulating theforce and direction of his breath so as to remove thesand without disturbing the gold. Where water GOLD. Ill can be had, a pan is the most efficient instrument aman can travel with in his gold-seeking journeys. A crude apparatus formerly much used in Cali-fornia and Australia is called the cradle or , as shown on Fig. 41, is a trough of some 7feet in length and 2 broad. Across the bottomof this several bars are nailed at equal distances,and at the upper end a kind of sieve is fixed at abouta foot above the bottom. This whole arrangement Fig. is mounted upon rollers. To operate the apparatusfour men are required. One man digs out theearth from the hole, a second supplies the cradlesieve with this auriferous earth, a third keeps up asupply of water which he pours upon the earth inthe sieve, while a fourth keeps the machine contin-ually moving upon the rollers. The large stoneswashed out are removed by hand from the sieve, 112 PROSPECTOR S FIELD-BOOK AND GUIDE. and the water at the same time washes the smallersubstance through, which is slowly carried towardsthe lower end of the trough by a slight inclinationgiven to the whole. Thus the flow of water tendsto keep the earthy particles in suspension so as toallow of their washing off, while the heavier por-tions of gold are obstructed in their flow, and re-tained against the cross bars fixed to the cradlebottom. These are removed from time to time anddried in
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectprospec, bookyear1903
