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1841.] THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. -t V 1 ) > Jt N.B.—The red flag, or ball, must be used in the day, in the same manner as the red lamp by night. Rockets or blue lights are extraordinary signals, and when an engineman sees them he must immediately stop to ascertain their cause. Engine Whistle.—7. ’When one long whistle is given, it is a signal to gate keepers, policemen, and others in front, that an engine is coming, and this signal is to he used on approaching public roads, during a fog, or when a first class train approaches a station where a second class train is stopping, and generally as a caution when required, for persons on the line to keep out of the way. But when an engineman wishes to make signal to the guards, or breaks- men on the train, that they are to put on their breaks and stop, he must give a quick succession of whistles, making an interrupted, tremulous, or vibrating sound; and all guards or breaksmen, whether with coach or luggage trains, hearing this signal, must immediately hold hard on the break or breaks under their charge, so as to stop the train as quickly as possible. NEW INVENTIONS AND IMPROVEMENTS. IMPROVEMENTS IN STEAM ENGINES. Thomas William Parkins and Elisha Wylde, of Portland-street, Liverpool, Engineers, for an improved method of making and working locomotive and other steam engines. Enrolment-office, Jan. 12, 1841. This improved method relates to the slide valve and throttle valves of steam engines, and consists in a novel mode of constructing them, so as to facilitate the action of the valves, to place them under more perfect control, and to afford a freer entrance to the steam cylinder under certain circumstances. The first arrangement is for working the slide valve without the use of eccentrics, in order that it may open almost instantaneously at the time the engine is passing the centre. For this purpose a lever is fixed upon the cross head working in a link connected to a second lever fixed on a shaft or weigh- bar across the engine, whereby a rocking motion is produced. On the other end of the weigh-bar a double lever is fixed, carrying two studs above and below the centre of the said shaft or weigh-bar, for the forked rod to work upon. One end of this rod is attached by a working joint to a fourth lever fixed on the weigh-bar, which gives motion to the slide valve at each succeed ing return of the cross-head to the extremity of its stroke. The levers are so arranged that the slide valve is always kept wide open at the period of the engine passing the centre, instead of being shut, as is always the case when an eccentric is used, and by which means the full effect of the steam is em ployed up to the last moment. Secondly, a new method of constructing the slide valve, being an improve ment upon the old D slide valve, is described; the object being to get rid of almost the whole of the immense steam pressure which always presses upon slide valves of the present construction, and at the same time to give a free passage for the escape of the waste steam throughout the whole of the stroke. This slide valve consists of a hollow' square ring of metal, working between two surface plates, the lower one being the side of the cylinder, the upper one provided with set screws or other suitable means of adjustment. The hollow ring beds upon the cylinder, and is furnished with a square metallic packing upon its upper surface, which, abutting against the adjusting plate, makes the slide valve perfectly steam tight. The slide valve is made long enough for the eduction passage to remain open while the steam way is closed, and vice versa. Thirdly, the patentee describes a peculiar mode of constructing the regula tor or throttle valve of steam engines, especially as applied to locomotive en gines, so as to afford a ready and convenient means of admitting steam to cither one of the cylinders only, or to both of the cylinders at the same time. The regulator or steam passage is in this case a flat surface, with passages through it at the distance of one end of the cylinder from the other, and so disposed that when the regulator’s handle is inclined to the starboard, steam is admitted into the cylinder on the larboard side of the engine; on inclining the handle over to the larboard, the steam is also admitted to the starboard cylinder, but on placing the regulator handle in a vertical position, the throt tle valve is closed, and the steam communication cut off from both cylinders. A fourth improvement consists in certain additions to the machinery for working the slide valve, so as to cause the steam to work in the cylinder ex pansively, in order to economise fuel; for this purpose two slots are made in the top of the link in which the cross-head works, in which two bell-crank levers work on pivots; to the under side of the engine framing, a roller is fixed between the two levers, being a fulcrum to act against when they are alternately pressed down by the roller (attached to the lever on the cross head), which works in the link passing over them; this causes the link to advance sufficiently to close the slide valve, or, in other words, to shut off the steam at the determined portion of the stroke. Finally, an arrangement is exhibited for reversing the direction of the steam, so as to stop the engine and drag the wheels whenever circumstances render such a procedure necessary. In order to accomplish this movement, a handle is placed on one side of the foot plate, which is connected to a bell- crank lever, connected by a link to the tappet-rod. This handle is to be secured by a spring guard, and when in a vertical position the tappet-rod will !L? be entirely out of gear; when it inclines forward, it will be in gear for going either forward or backward; and when it inclines backward, the tappet-rod will be lifted on to a stud on the third lever above the centre of the shaft connected with the link on the other side, which will stop the motion of the engine almost immediately, as the steam will he admitted into the cylinder before instead of behind the piston, which will drag the wheels and bring up* the engine. The claim is to 1. The construction of the slide valve, being a hollow ring through which the steam is either admitted or exhausted, and the means used for keeping the said slide valve steam tight. 2. The combination of the machinery for moving the valve, especially the construction of machinery for moving the said valve so as to work the steam expansively. 3. The construction of the regulator or throttle valve by which steam is admitted to either cylinder only, or to both cylinders at the same time. 4. The construction of machinery for moving the slide valve so as to cause the steam to enter the cylinder before instead of behind, and make it act against the piston.—Mechanics' Magazine. TOOLS FOR BORING. William Ash, of Sheffield, Manufacturer, for improvements in augers and tools for boring. Petty Bag Office, Dec. 24, 1840. These improvements consist in the combination of cutters and guides with a shank or spindle. The cutters are rectangular pieces of steel somewhat resembling the cutting side of a centre-bit. The guides are helical pieces on the outside, of various sizes, the interior of which fits the shank or spindle. The spindle has a pointed screw at the end, the size of the thread varying according to the kind of wood to be operated upon; at some distance up, on the side of the spindle, there is a circular stop, there is also a square opening just above the worm, passing through the spindle. The helical guide, of the size required, is first put on the spindle, and a cutter inserted in the square aperture below it, where it is firmly fixed by driving in a wedge. If a larger or smaller hole is required, the wedge is struck out, when the cutter, Ac. may be easily removed, and replaced with guides and cutters of the size re quired. Another form of guide is shown, consisting of a circular plate of metal, with a thimble in its centre, supported by two cross pieces from the outer edge. The first, or helical guide, however, is preferred, from its being longer, and also from its affording a channel for the ready escape of the chips, thereby clearing the hole as the cutter advances. The claim is for the application of moveable cutters and guides to a shank or spindle, as described.—Ibid. MACHINERY FOR CUTTING AND WORKING WOOD. William Hickling Bennett, of Wharton-street, Bagnigge Wells Road, Gen tleman, for improved machinery for cutting and working wood, Enrolment- office, Dec. 24,1840. The improvements comprehended in this patent are—Firstly, a new system of guides for boards while passing through the wood-cutting machines. The iron frame of the guides varies in shape in different machines; it forms a bed on which the guides traverse. The guides are formed of puppet-heads in pairs, one being fixed, the other moveable in order to hold and guide wood of different sizes. Moveable pieces slide over the inner vertical faces of the guides, and pressing down upon the upper surface of the wood it is thus held firm and steady. Secondly, an improved mode of elevating and depressing the upper pair of rollers, when the wood is carried forward by their means. The axes of the upper rollers turn in blocks which slide up and down in grooves in the up right side frames of the machine. They are regulated by spur and bevel wheels, in conjunction with spiral springs, so that while the wood is firmly held, an elasticity is obtained by means of the springs, which allows any irre gularities in the surface of wood to pass through the rollers. Thirdly, an improved mode of admitting oil to the working parts, viz., the circular saws, shafts, spindles, &c., consisting of a cup with a tube at the bottom furnished with a stop cock, to be so adjusted as to allow any number of drops per minute to fall from the nipple into the channel leading to the bearings requiring lubrication. Fourthly, an improved mode of sawing and dividing wood, so as to effect the planing at the same time; the arrangement being also applicable to veneer saws. For this purpose, there are slots near the periphery of the circular saws, approaching as near to the edge as is consistent with due strength ; in these slots side cutters are fixed, with their edges ground and set to the same angle as a plane iron. These cutters project slightly beyond the set of teeth of the saw; so that a shaving is continually taken off as the saw revolves. Or the edges of such slots in the saw plate may be turned up and used in lieu of de tached cutters. Fifthly, the application of the foregoing construction with two or more sets of circular cutters, so as to form two or more strips of plain or orna mental moulding. To accomplish this, two or more circular saws are mounted on one spindle between which, instead of washers, blocks are fixed, holding the cutters in the upper edges. These are circular and may he cither plain or moulded, and they project sufficiently to perform the necessary operation as rapidly as the circular saws can rip the scantlings or hoards into strips. Sixthly, an improved mode of forming moulding and other cutters. These cutters may he of any required shape, and are attached to blocks, fixed on