a semicircular trough, is kneaded or worked by a fluted roller, whilst several streams of water are permitted to flow upon it. The starch is thus separated from the paste, and is carried off, by the water, through two wire sieves (consisting of one hundred and twenty meshes to the inch), into two gutters, by which it is conveyed to a bucket, and is thence transferred into a vat or tub. After the starch has been washed, it is submitted to a slight fermentation, to destroy any gluten that may remain therein; then the washing is repeated, and it is dried by cold air, and finished by the application of hot air.

The gluten, &c., after the starch has been extracted, may be used in the manufacture of bread, biscuits, and every kind of pastry.

The second part of the invention consists in separating the farina from the residue of potatoes, after they have been peeled by the machine hereafter described; and in preparing the farina, for the manufacture of bread, &c., by breaking the envelopes of the small globules which contain it. The potatoes are first cleansed, by being passed through a" washer," consisting of a cylindrical framing, partly immersed in a vessel of water, and revolving upon its axis, in an inclined position; they are then stripped of their skins by a "peeler," which is a machine similar to the washer, but somewhat longer, and having its interior covered with metallic brushes; the skins, which will carry with them some portions of farina, sink to the bottom of the vessel. When the skins have been removed, the potatoes are submitted to the action of a cylindrical rasp, and carried from thence, by chain-cups, to an endless travelling sieve, upon which a number of jets of water act, and divide the farina from the residue. The envelope, or case of the farina, is broken by a slight washing in acidulated water, and the acidity, which it may imbibe during the process, is removed by rinsing in cold water; it is then dried by cold or heated air. Instead of this method, the envelope may be broken by crushing it, in a machine, with a metal roller or cylinder; or by submitting the farina to a heat of sixtyfive centigrades, or more.

VOL. XXII.

2 P

The last part of the invention consists in preparing the residue of potatoes for being used, with other materials, in making bread and sea-biscuits. After the residue is removed from the bottom of the peeler, it is bleached, by washing in cold water, and passed through a press; from the press it is removed to a drier, and thus the disengagement of its carbon is prevented. When the residue is dry, it is reduced to flour, by a mill, consisting of a grooved cylinder, working in contact (or nearly so) with a grooved plate; the latter is kept cool by a current of water, or cold air, at the back of it, and thus the flour is prevented from becoming heated during the grinding.

If the operator prefers to employ the residue in a moist state, as it comes from the peeler, it is passed through a press, and then mixed with the other substances used in making dough, before a sufficient time has elapsed for its carbon to become disengaged.-[Inrolled in the Inrolment Office, March, 1843.]

TO WILLIAM HENRY FOX TALBOT, of Lacock Abbey, in the county of Wilts, Esq., for improvements in coating or covering metals with other metals.-[Sealed 25th November, 1842.]

THE first of these improvements consists in preparing the surfaces of metallic articles, intended to be gilt, by giving them a very thin coating of silver. This may be done by dipping them into a weak solution of silver in hyposulphite of soda; but any other suitable method may be adopted.

The second improvement consists in a method of preparing the surfaces of metallic articles, which are to be gilt or silvered. When the article to be coated has been well cleaned, it is attached to one of the poles of a voltaic battery, and then both the poles are plunged into a vessel, containing a mixture of water with any suitable acid or salt. The battery is so arranged that decomposition of the water ensues, and the article gives off hydrogen gas for

some time; it is then quickly detached from the battery, and being thrown into a vessel, containing a proper solution of gold or silver, it receives a coat of one of those metals. It is after this washed in pure water; and this process is repeated, until a coating of sufficient thickness is obtained.

The patentee claims preparing the surface of articles, intended to be gilt or silvered, by causing them to give off hydrogen, being connected with the poles of a voltaic battery, as aforesaid.

The third improvement consists in gilding metallic articles by dipping them into a mixed solution, containing gold, and one of the baser metals; those metals being excluded which would precipitate gold.

The patentee claims, under this head, employing a mixed solution of gold, and one of the baser metals, (with the exception of mercury,) for the purpose of gilding metallic articles.

The fourth improvement consists in using a solution of chloride of gold, mixed with a solution of boracic acid, for the purpose of gilding articles of brass or other metal; by which means a more pleasing color is produced than when the chloride is used alone. Boracic acid may also be added to other solutions of gold.

The fifth improvement relates to a method of removing the dark tint which metallic articles acquire when they have been dipped into a solution of gold not altogether suitable for gilding. It is removed by dipping the articles into a very weak solution of nitrate of mercury, in water, which soon causes the surface to brighten; the articles may then be dipped into the solution of gold, and again into the solution of mercury, and so on, alternately, until the desired coating is obtained. Any excess of mercury may afterwards be removed by an acid, assisted by voltaic action.

The patentee claims the use of a solution, containing mercury, for the purpose of improving the appearance, or brightening the surface of articles which have been gilt imperfectly, or of too dark a color; and the method, above

described, for removing the excess of mercury from gilt articles, by voltaic action.

The last part of this invention has reference to the fact, that if metallic articles are dipped into a solution of silver, they only receive a coating of limited thickness; the effect ceasing after a time, and no more silver being deposited, in consequence of the metal, on the surface of the article, having become similar to that in the solution; but, if made again dissimilar, the effect is, to a certain extent, renewed. The improvement consists in creating such dissimilarity, by dipping the article into a different solution of silver, or into a solution of some other metal, and then replacing it in the first solution of silver; these dippings are to be repeated alternately. This method, of alternate dipping, may also be applied to the solutions of gold.

The improvements, above described, are more especially applicable to the coating of brass, copper, silver, German silver, iron, and steel.-[Inrolled in the Inrolment Office, May, 1843.]

To CHARLES ROBERT AYERS, of John-street, Berkeleysquare, architect, for improvements in ornamenting and coloring glass, earthenware, porcelain, and metals,—being a communication.-[Sealed 23rd July, 1842.]

THESE improvements consist in ornamenting glass, &c., by the application of color, in the state of powder, through perforated screens of metal, or other suitable material, or through lace, or other open fabric, in a similar manner to stencilling; or by impressing a design upon the glass, by means of an engraved or ornamented block, with any suitable adhesive matter, and then depositing the color upon it.

The mode of coloring glass, &c., by means of perforated screens, or open fabrics, is as follows:-A coat of adhesive matter (the patentee prefers essence of lavender) having been applied to the glass, or other substance, with a soft brush, the screen, or open fabric, is laid over it; the pulverized color is then deposited upon the screen, which, with

the superfluous color, is afterwards carefully removed, leaving only that portion of the color which has found its way through the perforations, and adheres to the glass; the color is then permanently fixed by "firing," as usual.

When wooden or other blocks are used, the design is printed, with adhesive matter, upon the substance to be ornamented, and the color is dusted upon it; those portions of color which are not deposited on the adhesive matter, constituting the design, are then removed by means of a pair of bellows, or in any other convenient way, and the remainder of the color is fixed by the " firing" process.

If it be required to ornament a convex, or other surface, not flat, yielding-screens, or patterns, are employed, such as ornamental lace, or perforated paper screens; these are employed as before directed, and, being left on the article, are consumed during the fixing of the color.

The colors used in coloring glass and china by this process, are, in all cases, those generally employed for the same purpose; and the method of applying color, which the patentee prefers, is by agitation in a closed box, so as to cause it to be held in suspension; the article being then placed at the bottom of the box, will receive an even deposit of color.

The patentee claims, Firstly,—the mode of coloring or ornamenting glass, china, earthenware, porcelain, and metals, by applying color, in the state of powder, through perforated screens, or through lace, or other open fabrics, when combined with the fixing of such colors by heat. Secondly, the mode of coloring or ornamenting glass, china, earthenware, porcelain, and metals, by causing the surface to be impressed with the desired pattern, by a wooden or other block, with adhesive matter applied thereto, and then dusting over the desired color, in the state of powder; when such process is combined with the subsequent process of fixing the colors by heat.-[Inrolled in the Inrolment Office, January, 1843.]