ing' the mitres of picture frames, &c., have been constructed, with more or less success. One of the first machines made had a motion directly vertical to the wood; this was secured by a pair of right- and left-hand knives fixed to a cast-iron block working in a vertical guide, and operated on by a lever; this gave an up-anddown or chopping' motion. The knives were set to an angle of 45°, but with a little alteration the angle could be varied, if desired. The knives required considerable care to enable them to cut any length of time, but some operators even now prefer this machine to others of more recent date.

Some six years since a patent for an improved mitreing machine was taken out by a Mr. Shute, of London, and we believe considerable numbers of this machine have been made. The improvement claimed is that, instead of the ordinary vertical action across the grain of the wood, the moulding to be operated on is set on edge and the knives made to cut in a diagonal direction, thus operating more or less with the grain of the wood instead of across it.

A double mitre-cutting machine has also been recently patented by Mr. Bowman, of London. In this machine two cutters are arranged in slides, working diagonally at right angles to each other; these cutter slides are worked by means of a lever and two toothed wheels, which gear into each other and into racks of corresponding pitch, which are fitted to either cutter slide. The knives are capable of cutting the moulding to a required length, and at the same time mitreing it.

Several other machines have been made, the knives being given a horizontal motion, &c., but we are afraid the machine has yet to be invented that will cut true

for a continuance without splintering or leaving ragged edges—say, bolection or gilt mouldings, for instance.

There are some few machines made for fret-cutting, boring, &c., by hand or foot power, but as they are chiefly used for light ornamental work, they hardly come within the scope of this work.

CHAPTER XXVI,

CORKWOOD-WORKING MACHINERY.

THE writer has recently spent a considerable amount of time in perfecting several machines for manipulating cork wood. This, owing to its elasticity and yielding properties when under the action of the cutters, is a difficult material to operate on. For rounding cork wood for bottle corks, bungs, &c., the best plan to pursue is to mount in an adjustable slide with a horizontal motion a plain steel knife some 18 inches long, which can be kept constantly sharpened by means of small revolving emery wheels bearing directly on its cutting edge. The cork wood to be rounded is secured between spring chuck centres, and when horizontal motion is given to the knife a rotary motion can be imparted to the cork wood by means of a lever and belt. The slide carrying the knife should be arranged to swivel, and be adjustable to varying sizes of corks, and also adjustable vertically at either end; thus by lowering the slide at one end and making the knife to traverse diagonally taper as well as cylindrical corks can be

Chucks fitted with several steel needle-points are to be preferred for general purposes, as the cork wood is very rapidly fixed in them and the slight indentations made by the steel points disappear. The chucks

employed are of course made to suit the different-sized corks or bungs required. Cork wood is often employed in sheets as lining for helmets, hats, socks, &c., owing to its lightness and protective powers. These sheets have sometimes to be produced as thin as paper, an operation of considerable delicacy. I have employed with success for this purpose a circular revolving steel knife ground sharp at its periphery, and the cork wood, which is cut in the first instance to the shape the sheets are required, is fixed in a movable chuck-plate, arranged to revolve by hand and fitted with an extremely delicate feed-motion for bringing the cork wood to the knife, or vice versa.

Cork wood is largely employed in the manufacture of different kinds of floor coverings, such as corticine, &c. For this purpose it is necessary to reduce it to the very finest powder, such as would pass through a 70-mesh sieve. The production of this must be set down as perhaps the most difficult of all operations in wood conversion. If it is passed through a highspeed disintegrator, making some 3,500 revolutions per minute, the bulk of the product is far too coarse for the purposes required. Ordinary edge-runners will, with sifting, produce the required fineness of powder; but this is at the best a very slow, and therefore an expensive, process. The writer has made a variety of experiments in this direction, which have more or less failed in their object; but he is now engaged in constructing a machine in which rubbing and cutting actions are combined, and he has so far every reason to believe this arrangement will have the desired result.

CHAPTER XXVII.

MISCELLANEOUS MACHINERY FOR WORKING WOOD.

A LARGE number of machines have been produced from time to time for performing the many special operations required in the conversion of timber. Many of these machines are made for or by the users, and often embody in their construction points of great ingenuity, which the owners keep to themselves. Possibly in these days, when the rule seems to be, 'Live on other men's brains if you can, if you cannot use your own,' they may not be much to blame in not making known an idea from which, owing to more rapid and economical production, they derive an extra gain. These inventions or improvements are usually made by small masters, or men operating the machines, who, owing to slender means, are unable to pay the high rate of patent fees in vogue in this country to protect their ideas, and have perhaps found to their cost, in conjunction with many others, that the recompense arising from working for the public good may be represented by the algebraic term z. America, on the contrary, rejoices in a low patent rate, and doubtless this has its objections; but we think it may be cited as one of the several reasons why America is enabled-although affording her producers a higher rate of pay-to compete