timber to be cut. They are, however, owing to the small size of our timber, little used in this country, and are generally known as American or Canadian rack benches, but were really the invention of Sayner and Greenwood, whose patent we noticed in our last chapter.

In our Exhibition of 1862 a considerable number of English, American, and Continental machines were shown. Messrs. Greenwood and Batley, Leeds, exhibited several very ingenious machines, including a curvilinear band sawing machine with a variable and self-acting radial motion, Kinder's shaping machine, &c. Messrs. Worssam and Co., London, exhibited a portable deal frame, band sawing machine, &c. Messrs. Powis, James, and Co., London, showed hollow-framed band sawing machine, planing machine, mortising machines, &c.; Messrs. Robinson and Son, of Rochdale, planing and squaring-up machine, tenoning machine, &c.; and a number of other machines were also exhibited by Messrs. McDowall and Sons, Glasgow; Kennan and Sons, Dublin; J. and T. Young, Ayr; Haigh, Oldham; Geeves, London; Weston and Horner, London, &c. A new tree-feller was shown by Mr. R. Thompson, of Woolwich. These machines, taken as a whole, were considered fair examples of design and workmanship, but were far behind those of the machine tool-makers in the massiveness of their framing and general compactness and simplicity of their details.

Amongst the Continental machines exhibited was a band saw and traversing mortising machine, by M. Périn, Paris, the former of which attracted a great deal of attention, chiefly from the very able manner in which

it was worked. Messrs. Bernier and Arbey, and Messrs. Varrall, Elwell, and Poulot, of Paris, and M. Zimmermann, of Chemnitz, also showed a varied collection of wood-working machines, but nothing calling for special notice.

Immediately following the Exhibition, what must be considered one of the greatest improvements ever introduced in connection with wood-working machinery was brought out by Mr. Henry Wilson (then manager of the firm of Powis, James, and Co., London). This was what is known as the solid or 'box' framing-that is, instead of the frames of saw benches, moulding machines, &c., being bolted together in pieces, they are cast in one solid mass, thus securing greater rigidity, enabling saws, cutter blocks, &c., to be driven at a very high velocity without vibration. This was unattainable in machines hitherto made with light iron or wooden framings, although in former years it was argued that wooden framings were preferable to iron, the vibration of high-speeded cutters being absorbed by the elasticity of the wood. The fallacy of this reasoning has been amply disproved by the almost universal adoption of solid iron framings in this country, and more or less in America and on the Continent, America hitherto being the great advocate for the use of wood. Wooden framings might have the advantage of lightness and portability when used in unfrequented countries, and also be somewhat less in first cost, but where machines are fixed for permanent use there seems to be little doubt that solid iron frames are in every way preferable, being stiffer and steadier in their work, much more durable, and costing less for repairs. A number of other improvements were about this time introduced by Mr. Wilson,

including a machine for sawing, adzing, and boring railway sleepers, for which he obtained a patent in the year 1864. The arrangement for sawing was briefly as follows: Endless belts carried the wood between uprights, the width of the rough sleeper to be prepared ; six circular saws were erected, under which the belts carried the sleepers; the two outer saws cut the sleepers to the length required, while the other four saws were set in pairs and the proper position for making cuts to a certain depth in the sleeper, between which cuts, towards the ends of the sleepers, the wood is to be removed for the chairs to be seated. The belt then carries the sleepers under the adzes or sets of cutters revolving horizontally, whereby the wood between the two cuts last mentioned is removed, and the seats for the chairs are formed. The sleepers thus prepared are carried by endless belts to the boring machine, which is arranged to bore the four necessary holes in the sleepers either vertically or at an angle; after boring they were shot from the machine by the belts.'

Immediately following the Exhibition, Mr. W. B. Haigh, of Oldham, introduced various improvements into sawing machinery, including the mode of operating saw benches for cross-cutting purposes, in which, instead of making the bearings stationary which carry the spindle of the saw, they are made movable, so that the saw can be raised and lowered as desired. The driving band passes from any driving pulley over a carrier pulley, and around two other pulleys, and as one of them is central with the axis of a swing lever, the length between the two pulleys is the same at any position of the saw, and the tension of the band is the same in all positions. In large circular saw benches

the swing lever is moved up and down by a worm, gearing into a worm wheel or quadrant fixed to the boss of the swing lever, so that when the worm is turned either by hand or steam power one way, it will cause the worm wheel or quadrant to revolve and depress the swing lever and bring the saw below the table, in order to prevent accidents when the timber is being placed on the table, and when the worm is turned the other way it will bring up the saw and cut the timber as it rises, and, after the timber has been cut, the saw can be again lowered to be out of the way during the removal of the cut timber. In smaller saw benches the swing lever is moved up and down by a screw and nut or other convenient means.

A patent was also obtained by W. Jeffery, Glasgow, for an improved saw bench for cross-cutting purposes. In this machine the saw spindle was mounted in a slide, to which was given a self-acting reciprocating motion, by means of screw and bevel gear, arranged to reverse automatically by means of a weighted lever and stops. A slide plate could also be used for cross-cutting, the saw remaining in a fixed position. The wood was held against a fence on this plate, and pushed through the saw by hand, a weight attached to the sliding plate bringing it back to its original position after each cut.

Mr. Samuel Worssam, in 1865, patented an improved self-acting saw bench. The improvements related to the mechanical arrangements for moving the timber on the saw bench, consisting chiefly in the use of movable feed rollers and a pair of rotating rollers for returning the timber to its original position on the bench when a plank had been sawn therefrom.

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Of the great variety of wood-working machines, the circular saw bench, in its many forms, is the one, perhaps, in most general use in all parts of the world, as before the wood can be submitted to any other process, such as mortising, moulding, &c., it must first be prepared on the saw bench. It is, therefore, of the highest importance that it should be well proportioned and adapted to the special class of work it has to perform; but this is far from always being carried out. We take it that true proportion denotes the just magnitude of the members of each part of a machine, and the relation of the several parts to the whole. If this was more generally borne in mind, we should not, I think, see so many abortions' turned out by so-called 'engineers,' which has taken from English machinery more or less the high character it once held, and has in several classes of industry proved a boon to our American rivals.

In wood-working, as well as other machinery, great care should be taken in designing; a certain weight of iron, correctly apportioned to bear the wear and tear, and high speeds it is necessary to run at, is far better and more economical than twice the amount of metal used haphazard; but how rarely does this matter receive the attention it deserves. With some makers it seems that so long as a machine may be made to work after a fashion and sell at a certain price, their end is attained. This may be satisfactory to their pockets, but it certainly cannot be considered as conducive to true engineering progress. Of course there are some notable exceptions, and I think I cannot do better than refer to Sir Joseph Whitworth's machine tools as illustrating great excellence of design and proportion, and