The plough shown by Fig. 21 is for use with the lying press shown by Fig. 13, p. 18. It has a screw A made by threading from one end to the other a piece of iron wire about No.4 B.W.G., 8 in. long. Fix a washer at F with a bit of solder, leaving enough of the wire projecting beyond it to pass through the hole in the flat bar and for a thumb-bolt E to screw on. The wing-nut can be made of brass, with a rounded neck and flat wings. Drill and tap it to screw tightly on to the wire, and leave it before fixing it on while the bar B is made. Procure 8 in. of ¼ -in. by ½ in. flat iron, and bend about 1-in. up at one end, as shown in the sketch. File it up perfectly true and smooth all over, and then drill a hole at F for the- screw to pass through easily, and drill and countersink two holes at the other end for the heads of two Ii-in. screws to drop in. 0 (Fig. 21) is the sliding block, and D is an end view of the runner block. It is important that the sliding block (Fig. 22) be accurate. Get a block of brass 1 in. by 1 in. by It in., carefully square it up, and then round the top comers a little, as illus­trated. Cut an oblong hole ½ in. by ¼ in. at B for the bar B (Fig. 21) to pass through. If two holes (not quite ¼ in. in diameter) are drilled through side by side, it will be easy, with a small chisel and file, to cut the hole to the desired shape. See that it fits the bar well-not loosely-and then drill and tap a hole at A the same size as the screw already made. If the block is slid along the bar till it is against the bit that is turned up, the proper position for the hole will at once be found by passing a needle through the hole already in the bar and marking a corresponding circle on the block c. If any doubt exists about getting these holes through accurately, mark the block on both sides, and drill also from both sides till the holes meet in the middle. Next cut the slot C 1/16 in. deep and ¾ in. wide, dovetailed to fit the bar B. Bevel a bit of good steel, ¾ in. broad and 1/16. in. thick, to fit in the block tightly, and, while it is in, drill and tap a hole through it, and also into the block, so that a small screw may be inserted to keep it from slipping out when it is in use. Make a small screw for the purpose just stated, and then proceed to finish the knife (Fig. 23).

Be careful, when the screw is put into its place, that it does not project above the surface of the knife, or it will tear the edges of the book as it passes to and fro when in use. The knife is now rounded at the end, as seen in Fig. 23, and then bevelled off to the shape shown. Fig. 23 represents it as it would appear if looked at from underneath. When it has been nicely tempered, it may be fixed in its place in the block. A piece of flat iron, 2 ¼ in. long and about ½ in. broad, forms a support for the end of the long screw. This is shown at G (Fig. 21). Near the top drill a hole in which the screw A revolves, and make two holes for the screws which fix it in its place, and the various parts of the cutter are ready to be put together. Slide the block c on to the bar B and the long screw A, and fix the wing-nut on the end by screwing it on tightly, and then secure it by passing a small screw through the neck into the screw A. Now fix the bar on a piece of 2-in. by 1 ½ -in. wood about 8 in. long and screw on the guide-plate G. It will be advisable to fix on two pieces of metal, as in Fig. 13, to keep the cutter from twisting. This tool will cut through any book as perfectly as one costing a hundred times as much. Still another kind of plough, resembling one pre­viously described, however, is illustrated by Fig. 24. To make it, obtain two pieces of seasoned beech for the sides A, about 8 in. long by 4 in. deep, and 1 ¼ in. or 1 ½ in. thick; also obtain a ¾ -in. iron screw and nut with tail, to insert in the side opposite to the handle. By using a wooden screw, a hole could be tapped in the side piece, and the trouble of inserting the iron nut would be saved. Two guides c, say 10 inches long and 1 in. square, are fixed in the handle side, say 1 ½ in. from the bottom: they slide through square holes. A notch is made to receive the cutting knife, as shown at E, so that when put on with two screw nails the knife is flat with the wood, as will be seen. To ensure movement in both directions, a hole is bored through the screw spindle for the pin and washer. The side now is all of one piece, and will move out or in as required. It remains to put a slip of wood or iron on the other side, so that it may hold on to the press bar B while working the plough backwards and forwards to cut the edge held in the press. This hardwood slip is shown at D. x (Fig. 24) is the iron which carries the knife, the shape of which is indicated by Y.

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