220 Class 5.— MACHINES FOR DIRECT USE, INCLUDING CARRIAGES, [United

North Areas A. B. 10 to 34 ; C. D. E. 1 to 10, & 19 to 33 ; F. 1 to 32 ; G. H. 1 to 13, & 19 to 26.

point of the moving line will describe a circle. Thedistance between the top of the cylinder and the axis ofthe shaft need not to be more than half the length of thestroke. This permits the machinery to be comprised ina very small compass. The friction on the slide is incon-siderable, and vanishes altogether when the engine isproducing its maximum effect. The motion is producedby a combination of levers, identical in principle with thecommon crank. This crank, called the sliding crank, isequivalent in power to a common crank of the sameradius, having an infinite connecting-rod, and the parallelmotion of the connecting-rod is exact.

58 Whitelaiv, James, Johnstone, Renfrewshire,Scotland —Inventor.

Improved steam-engine, for driving the screw-pro-peller direct, without wheels or other intermediategearing, and for all kinds of machinery which work at aconsiderable speed.—(Drawing.)

Centrifugal atmospheric churn.—(Model.)

Centrifugal pump, for short lifts.—(Model.)

60 Wilding, William Henry, 2 Chesterfield Street,

King’s Cross —Inventor.

Patent steam-engine, exhibiting a new method of con-verting reciprocating rectilinear motion into rotatorymotion. Model, illustrating a modification of the same.

Model of a patent submerged paddle-wheel, combiningthe power of the ordinary feathering wheel, with the-advantages of the screw, in being wholly under water.

61 Leigh, Evan, Miles Platting, Manchestei —Inventor.Patent steam-engine.

63 Williams, D., Thornhill, Llandilo, Wales—Inventor.

A furnace, for burning anthracite or smokeless coal, inmarine, locomotive, and other steam-engines.

64 Dodds & Son, Rotherham —Inventors & Manufacturers.

Four-horse portable steam-engine ; for all purposes

to which portable engines are usually applied, hut moreespecially for thrashing, &c. The particular features are,the direct motion given to the slide-valve by a returncrank, and the arrangement of the cylinder face andvalve, without the intervention of other machinery thanthe valve connecting-rod, no weigh-bar or cross-shaftbeing required; it is also easily accessible to repair.

Model of locomotive engine, without boiler, fitted withthe exhibitors’ patent wedge expansive (cam) motion.Its simplicity consists in having only two eccentrics,instead of four, for working the valves, the strokes ofwhich are adjusted or reversed by means of wedges orinclines ; the motion to the valve is direct (without weigh-bars or other intermediate machinery, except the valveconnecting-rod).

A piece of Jessop’s patent steeled tire-bar, for railwaywheels. The wearing surfaces of the tire are convertedinto steel (either in the bar or after being welded into ahoop), but only so far as is necessary to maintain theworking surface, by which all the toughness and ductilityof the iron are retained, while the steel parts may behardened and ground up.

A piece of railway bar, with the wearing surfaces con-verted into steel by Jessop’s patent process. Beingsteeled, the bar is of greater strength and durability; itdoes not laminate or splinter, and it presents a uniformhard-wearing surface. The process is believed to increasethe strength of wrought-iron, and consequently allowsrails to be made much lighter.

Model of a railway bar straightening press, on truck.The straightening press does not indent the surface ofthe rail, as the hammer does, and will straighten muchquicker.

65 Scrmon, Henry, & Co., New North Road, IIoxton —

Manufacturers.

Jttkes’s patent smoke-consuming furnaces.

66 Redmond, Amedee Francois, Birmingham —Importer and Inventor.

Working model of a steam-engine, showing three dif-ferent constructions of slide-valves: short slide, and longD valve; and the exhibitor’s patent double independentslide valve, to prevent back pressure from the exhaustedsteam. This model is worked by steam, and is furnishedwith an indicator, to show the comparative effect of dif-ferent slide-valves.

67 Ebbw Vale Company, 83 Upper Thames Street, and

Abergavenny —Producer.

An improved double-cylinder steam-engine, one-horsepower. Invented and designed by Evan Williams, a blindman. _

68 Clay, John, Edgeley, Stockport —Inventor.Smoke-consuming furnace.

69 Whitney, James, Calver Hill, Hereford —Inventor.

Apparatus for preventing the bursting of steam-engineboilers, and other steam apparatus, by an improvement inthe composition and adaptation of fusible metallic plates.

70 Constable, William, Photographic Institution,

57 Marina Parade, Brighton —Inventor.

Model of the “ Compensating Fly-wheel,” an inventionfor converting a fluctuating into a constant force.

The fly-wheel, as ordinarily applied to steam-engines,effects two purposes—it carries the engine through thedead points of the crank revolution, and it does thiseffectually: it also, in a measure, corrects the variationsinseparable from a power communicated through a crank.This latter service, however, it performs only approxi-mately, and being fixed upon the main shaft, it transmitsall its uncorrected irregularity through any train ofmachinery connected with it, in many cases to the greatdetriment of the manufacturing work it has to perform,and often occasioning the rapid destruction of the gear-work through which the power is transmitted. Thisdefect is incurable under the existing method of usingthe fly-wheel; for although every augmentation of itsweight will bring its oscillatory movements within a morelimited range, yet no weight of metal will ever entirelycorrect them. In the scheme involved in the model, thehopeless task of compelling the fly-wheel to steadiness isabandoned, it being permitted to take up its oscillatorymotion according to the force applied, while all thesubsequent machinery is secured from partaking, in theslightest degree, of these oscillations.

The means for effecting this consists in releasing thefly-wheel from its rigid connection with the main shaft,and substituting for it a spring or springs, through whichthe force is conveyed, and then, by a further device,correcting the small remaining irregularity that resultsfrom the reaction of the springs when under differentdegrees of enforcement. It will be apparent to everymechanic that constructive arrangements comprehendingthese principles of action may assume a great variety offorms and combinations. The following is that adoptedin the model, the essential parts of which are shown inits accompanying diagrams. It consists of a fly-wheel3 feet in diameter, having six arms, hanging loose upona cylindrical end of the main shaft; immediately behindthe. fly-wheel are three other arms, issuing from a bosswhich is fixed on the same main shaft. On the face ofeach alternate one of the fly-wheel arms there lies a spiralspring, which is partially compressed between two studswhich are fixed to the arms of the wheel; a bolt passesfreely through the springs and studs, which being drawnupwards (towards the rim of the wheel), forces thespring, by means of a collar at the lower stud, into closercompression. The bolt is connected with the roller on therim by a leather strap; the spindle of this roller passesthrough a hole in the rim, and carries, on the other side, asecond roller, which, in like manner, is fastened by a secondstrap to a pin at'the upper end of an arm of the boss.

The fly-wheel, during the part of its revolution in