from a square-sided piece of wood, a large percentage therefore being entirely wasted. These bevelled pieces are easily fed through a moulding machine by substituting for the ordinary parallel feed-rollers narrow rollers, with their periphery serrated and sharply bevelled. Short driving belts are to be avoided in every way, as they simply mean great increase of friction, and consequent deterioration to belt and bearings, with increased difficulty of lubrication. The belting used should be uniform in thickness, and kept as pliable as possible, and sufficiently wide to prevent over-straining. After repeated experiments I can recommend that driving belts should be run with their outside or smooth surface to the pulley, which is directly contrary to the plan now usually pursued, the practice being to run the rough or flesh side of the belt on the pulley. I have found that if a belt is evenly made, and smooth on its face, it bears equally over the whole face of the pulley, and not at certain points, as in the rough surface of the flesh side of the leather. With a smooth belt the air is almost entirely excluded, and the driving power considerably increased. To produce a smooth and perfect surface on the wood when planing, much depends on the accuracy with which the knives are sharpened and adjusted on the cutter block. A straight-edge or square should be used to try them at all points. The usual plan of trying them on the wood is not, as a rule, sufficiently accurate. Bottom cutter-blocks are easily adjusted by laying the straight-edge over the opening through which the cutters project, and making each knife touch exactly at every point the edge of the straight-edge. Duplicate sets of tools should be kept on hand in case of accidents. Automatic lubrication

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should be employed wherever possible, and none but the best lubricants employed for high-speed spindles. All open oil-ways should be protected from dust; the bright parts of machines not in use should be coated with a mixture of white lead and tallow. At least half an hour should be spent at the end of each week in thoroughly cleaning the whole of the working parts of the machines, and the framework should occasionally be painted. This not only preserves the iron, adding to the appearance of the mill, but encourages the workman to take a pride in the condition of his machine. These points are, however, often neglected.

CHAPTER XXXI.

MACHINES FOR ESTATE PURPOSES.

THE use of wood-working machinery is gradually extending to that class of work required on country estates-viz. the conversion of timber grown on the estate into boards, gates, posts and rails, fencing, &c., and other articles required in the farm buildings and cottages. Even on estates of moderate size-say, above one thousand acres-steam can doubtless be employed profitably in wood conversion, as, should an engine be used—as in these days of high farming is generally the case for preparing cattle food, it can be devoted at least one day a week to wood-cutting, and even at this rate will pay a fair interest on the very moderate outlay necessary. Except on large estates, and where skilled men are constantly employed, machines of the plainest and simplest kind are to be preferred, as joinery and mouldings, &c., can usually be purchased cheaper than they can be prepared, at any rate in small quantities. The most convenient machine to use is a plain circular-saw bench, or one fitted with selfacting feed where heavy timber is used. The frame of this bench should be on the box' principle, and especially strong to withstand rough and unskilful usage. The saw spindle should be arranged to rise and fall, so that

the driving pulleys may be lowered below the level of the table, so that the whole width of the bench may be utilised for cross-cutting posts and rails, fire wood, &c. A sliding plate, working in a dovetail groove on the top of the bench, running parallel to the saw, and fitted with a cramp for securely holding the wood, should be employed where much accurate cross-cutting is required, such as wood blocks for paving purposes, &c.

The saw fence or guide should be arranged to turn over the end of the bench, out of the way, when not required for straight sawing. The saw spindle should be bored at one end to receive augers for boring or slotmortising purposes. For estate purposes the addition of a mortising table is of great value. This is best added by arranging the frame of the bench on one side immediately below the saw spindle, with planed strips to receive a sliding table or bracket, which can be raised or lowered vertically by a rack or screw. On this table is fitted a slide, arranged with lateral and transverse movements, and a cramp holds the wood firmly whilst under the action of the mortising tool. The mortises are produced by a revolving routing or slot-mortise tool, the slide carrying the wood at the same time receiving a traverse motion by means of a hand lever. The lengths of the required mortises are governed by adjustable stop-pieces, and the transverse movement of the slide, which is usually worked by a hand wheel and screw, gives the required depths.

Should a further range of work be required, an arrangement for cutting tenons, striking mouldings, or planing can be added. Except where a permanent sawmill is established, the portable engine is the most useful form to employ for estate purposes.

CHAPTER XXXII.

FRAMINGS OF WOOD-WORKING MACHINES.

WHEN considering the different classes of machines, we have from time to time given hints as to their framing and general construction; but as wood-working, unlike most other machinery, is subject to excessive and constant strains, it may not be out of place to discuss the matter a little more fully. In addition to the ordinary strains of tension, pressure, or shearing stress, the framings of wood-working machines are subject to an especially severe vibrating strain, arising from the high speeds, arduous duty, change in velocity or direction of motion, which the spindles or working parts are subject to. The ordinary rules for calculating the elastic or breaking strain of the materials employed when designing framing must be considerably modified, allowance being made for excessive vibration, and in some classes of machines for the heavy load, in addition to the ordinary working details the framings have to carry. As we have before mentioned, for some years the framings of wood-working machines were constructed almost entirely of wood, the theory being that wood, being elastic, would, more readily than iron, absorb the excessive vibration. Practical experience has, however, sufficiently disproved this