Iron spindle (F) 1 ft. 6 in. long, with ‘lap’ (M), screw and nut (P), reel (G). Four circular laps will be required, each with its own spindle, screw, nut, and reel. The reels must be exactly the same size, so that the strap may suit them all alike. One lap is of lead, one of beech wood, one of pewter, one of deal with two layers of common felt strained over and neatly fastened with tacks on the under-side. Each lap is 10 in. in diameter, 1 in. thick at the edge, gradually sloping up to 11⁄2 in. towards centre. Spindles 1 in. square, rounded to sharp points at both ends. Reels 2 in. in diameter, of elm or box, fixed 3 in. from lower point of spindles. The laps are screwed on the spindles as shown in [Fig. 1], where all measurements are given.
There is a circular hole in the floor of the bench to allow spindle and reel to pass in and out, 4 in. in diameter. The clamp (I) rises 13 in. above the floor of the bench, and is screwed into position by movable nut underneath. The movable arm (K L) is raised or lowered at will, and adjusted by screw and nut (Q). Length of arm from K to L is 71⁄2 in. A block of lignum vitæ (R) is inserted in arm. Blocks of the same wood are screwed on at S and T for the points of the spindles to work on. These points should be very sharp and only just ‘bite’ the wood, so that friction may be diminished as far as possible. When a hole is worn in the lignum vitæ the spindles can be shifted to a fresh part.
Fig. 3.
The spindle of the large iron wheel is made round at D, [Fig. 3], where it works in the floor of the bench. That hole should be lined with soft leather, fitting the spindle like a glove, and kept well oiled. An iron plate (A) keeps the spindle in position. The spindle is, of course, square where the crank grips it at B, and a nut (C) screwed tight keeps the crank in position.
The legs of the bench are let into sleepers (X Y, [Fig. 1]), screwed firmly to the floor of the room, and clamps at C and elsewhere screwed to the wall of the room may give additional rigidity. The bench must stand true and fast, so that there may be no oscillation during work. It should be placed in front of a window, as plenty of light is desirable.
The following requisites must now be procured. Seven pounds of emery ‘46-hole’; some fine sifted silver sand; some rottenstone in lumps—the hardest is best; some putty powder. Then you will want a housemaid’s blacklead brush, a nail brush with handle, a brush used for cleaning silver plate. These should be old and nearly worn-out. A large earthenware vessel for water to stand on a stool or table at the right side of the bench within easy reach, and three jampots for water. You see that the furniture is of the humblest description.
All being now ready, we may hope to commence operations in polishing a pebble.