In this way the domestic may easily adjust the door to any desired extent of opening; as a slight pressure in either direction will cause its upper edge to slip along the detent undulations to the required position. Fig. 2, is a view, shewing, on a larger scale, the details of the hinge of the draught door. The overhanging door a, is in this case hinged at b, by a pair of side pivots, which rest in recesses in a hinge support c, one on each side of the grate; and d, is the prolongation of the door below the joint or centre of suspension.

The patentee claims, First, the application and use of an overhanging back door, for obtaining two separate vents or passages for the products of combustion. Secondly,—the system or mode of arranging and constructing fire-grates and fire-places, wherein the front or main draught, and the back or secondary draught, are simultaneously adjusted and regulated. Thirdly, the system or mode of carrying off the dense smoke and vapours of fuel, by a back or secondary draught, as hereinbefore described. And, Fourthly, the application and use of a detent link or holder, with undulating notches or holding surfaces, acting in both directions, by the use of lateral or simple pressure only, as hereinbefore described.

To JOHN MACMILLAN DUNLOP, of Manchester, engineer, for improvements in the manufacture of wheels for carriages. [Sealed 1st October, 1852.]

THIS invention consists in manufacturing the tyres of carriagewheels of decarbonized or annealed cast-iron, into which rings of vulcanized or other compounds of India-rubber are inserted.

In Plate IV., fig. 1, is a front view of a wheel constructed according to this invention; fig. 2, is an end view; and fig. 3, is a section of a portion of the tyre, shewn on a larger scale. a, is the tyre, made of decarbonized or softened cast-iron, and cast with a groove, to admit the ring of vulcanized (or any other compound of) India-rubber b. This India-rubber ring is kept in its place by the pins c, passing through and projecting beyond it, and entering into the recessed part of the groove in the tyre, as shewn at fig. 3. The patentee remarks, that the tyres may either be cast separate, as shewn, and put on to the wooden felloes of the wheel, in the usual manner, or the tyre may be cast with the nave and spokes, if the same should be found preferable. He also states, that he lays no claim to the employment of India-rubber rings as tyres for

wheels; but he claims the combination of rings, made of vulcanized or any other compound of India-rubber, with decarbonized or annealed cast-iron tyres, as hereinbefore described, or any modification thereof.

TO THOMAS BARKER WALKER GALE and JONATHAN FENSOM, of Homerton, in the county of Middlesex, engineers, for their invention of improvements in the means of joining or coupling bands or straps.-[Sealed 6th October, 1852.] THESE improvements consist in the means of joining or coupling bands or straps; and have for their object, to join or couple the ends of bands, used in driving machinery, in a more convenient and expeditious, and consequently more economical, manner, than by the plans hitherto in use. Instead of joining these bands by means of lacing or studs, as is usually the case, the ends of the bands to be joined are firmly held together by two metal plates, one of which carries sockets, furnished inside with female screws, and the other plate has holes made through it to receive screws, which screw into the sockets of the other plates. The ends of the bands to be joined or coupled having been placed between these two plates, and the screw sockets passed through the holes made therein, the screws or bolts are screwed up tight, and the ends of the strap or band are thereby tightly squeezed between the two plates by means of the male screws of the upper plate.

The figure in Plate V. shews in section one of the improved couplings intended for a band, to be used with a flat-faced rigger a, a. a*, a*, are the metal plates, and b, b, the sockets, fixed on the lower plate a*, which is also covered with leather, gutta-percha, or some other suitable material, in order to prevent the metallic surface of the plate from coming in contact with the periphery of the pulley or rigger to which the band or strap may be applied. The sockets b, b, pass through holes made in the band or strap c, c, and they should be made of such a length as to admit of the band or strap c, being tightly pinched between the plates a, and a*, when the male screws d, d, are firmly screwed up. For coupling broad bands or straps, or when the band is to be applied to round-faced riggers, it is preferable to divide the coupling into two or more parts, so as to admit of its bending or yielding when at work, or to cause it to embrace and fit the round face of the rigger more perfectly. The internal construction of the coupling is precisely the same as the one above described.

The patentees claim, joining or coupling bands or straps by means of two metal or other plates, which are made to embrace the ends of the said bands or straps, and squeeze them tightly together, as above described; and, whether such plates be covered or not, to prevent metallic contact with the rigger.

TO WILLIAM OXLEY, of Manchester, merchant, for improvements in apparatus for heating and drying.—[Sealed 1st October, 1852.]

THIS invention consists in causing currents of air to be heated by steam or other medium, when passing through different series of tubes contained in a cylindrical or other shaped box; also in collecting the said heated air in a chamber, in which it becomes mixed to a uniform heat, previous to entering another series of tubes.

In Plate IV., fig. 1, is a side elevation; fig. 2, an end view; fig. 3, a transverse section; and fig. 4, a plan view, shewn partly in section, of the improved apparatus. a, is the exterior casing; and b, c, d, are three cylindrical boxes, placed within the casing a. The lower boxes c, and d, are secured at both ends to the end plates of the casing; but the box b, is somewhat shorter than the other two; the object of which will be hereafter explained: b*, c*, and d*, are tubes in the boxes b, c, d. The air to be heated is forced through the tubes b*, c*, d*, by means of the fan e. f, is a mixing chamber, in which the air, after passing through the tubes d*, and being partially heated, is mixed to a uniform temperature before it enters the tubes c*; and g, is another mixing chamber, connecting the tubes c*, to the tubes b*. The steam or other medium, by which the apparatus is heated, is admitted into the box b, by the pipe h; and, after circulating among the tubes b*, is conducted by the pipes h*, to the boxes c, and d, as shewn at fig. 3. i, i, are pipes, furnished with dampers, through which the heated air is conveyed to the drying frames, or disposed of as may be required.

The operation is as follows:-Steam or other heating medium having been admitted to the boxes b, c, and d, motion is given to the fan e, and the air to be heated enters into the casing of the fan, through the openings e*, and is forced through the tubes d*, in the chamber d; then through the mixing chamber f, into the tubes c*, in the box or chamber c; from whence it passes through the mixing chamber g, to the tubes b*, in the box or chamber b. The air, on leaving the

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tubes b*, which are fastened in the end plate a*, enters the space between the exterior of the boxes b, c, and d, and the interior of the casing a; from whence it is drawn off through the pipes i. In some instances the outer casing may be dispensed with, and the heated air conveyed direct from the tubes b*, to the object or room to be heated or dried.

Figs. 5, and 6, shew a modification of the apparatus for heating and drying; fig. 5, being a side elevation of the apparatus, and fig. 6, a sectional plan view of the same. The principal difference between this and the apparatus above described, is, that in the present instance, the series of tubes and the mixing chambers are all in the same line. k, is the outer casing; l, m, and n, are three series of tubes, separated from each other by the mixing chambers o, and p; q, is a fan, for creating a current of air; r, is the pipe for conveying the steam to the tubes through which the air passes; and t, the pipe which conveys the heated air to the object or apartment to be heated or dried. The pipe r, is placed in communication with the tubes n, in order to give the greatest amount of heat to the air, as it leaves the apparatus, and to connect the series of tubes 1, m, and n, by the double branch pipes 8, 8; but this arrangement may be varied according to circumstances. It will be necessary to place taps (which are not shewn in any of the figures) near the bottom of all the boxes containing the tubes, to let off the condensed steam.

The patentee remarks, that in some cases, it may be preferable to produce the current of air to be heated, by placing the fan in the off pipe, and thereby drawing it through the tubes; and it may also be desirable to increase or diminish the number of boxes containing the tubes, in order to adapt the apparatus to particular purposes.

The patentee claims, heating air, by causing it to pass through series of tubes, connected with each other by mixing chambers, as hereinbefore described.

To HENRY MORTLOCK OMMANEY, of Chester, for an improved furnace for melting of metals in crucibles.-[Sealed 1st October, 1852.]

THIS invention relates to an improved furnace for melting metals in crucibles, and consists in arranging or building the furnace in compartments, in such manner that the coke is not brought into contact with the crucibles. For this purpose the furnace is constructed with two or more compartments; but three or four are found to be more desirable. If three or four

compartments are used, one of them is called the "crucible chamber," into which the flues are directed from the other two or three compartments, which may be called the coke chambers, and which are ascertained to be more advantageous when fed from above.

This arrangement of using three or four chambers is found to be the means of effecting a great saving of time, labor, and materials over the furnaces which have hitherto been employed to effect the same purpose.

To GEORGE GWYNNE, of Hyde-park-square, in the county of Middlesex, Esq., and GEORGE FERGUSSON WILSON, of Belmont, Vauxhall, in the county of Surrey, managing director of Price's Patent Candle Company, for improvements in treating fatty and oily matters.-[Sealed 4th January, 1853.]

IN commencing their specification, the patentees remark that they have found that fatty and oily matters, which have been treated with powerful acids, do not burn well, or distil freely, owing, as is supposed, to a combination or intimate mixture of the acid with the fatty or oily matter. The present invention is designed to decompose, separate, or remove the above-mentioned combination or intimate mixture; which decomposition, separation, or removal, is effected by operating on fatty and oily matters, that have been subjected to the action of powerful acids, by boiling such matters in water, or water mixed with acid, or by steam, or watery vapour combined or free.

Let it be supposed that palm oil is the material to be operated upon, and that the agent to operate with is sulphuric acid:-The palm oil is to be kept at the temperature of about 150° Fahr., until the impurities, mechanically mixed with it, have subsided. It is then to be pumped up into large copper vessels, similar in shape (only much larger, and without the condensing apparatus) to the stills described in the specication of a patent obtained by the patentees in November, 1843. These vessels, which are called acidifiers, are to be connected together in pairs, in such manner that the steam may be turned from the one acidifier to the other when required: by this means a considerable economy of fuel will be obtained. When the temperature in one acidifier attains about 300°, the steam which issues from it is to be let into the adjoining vessel, also containing palm oil. Instead of