To HENRY BROWN, of Derby, for Improvements in the Construction of Boilers, whereby a considerable saving of Fuel is effected, and Smoke rapidly consumed.

THIS invention consists in the introduction of an additional tube to be filled with water by means of pipes passing from the boiler, which tube, by being carried through the furnace under the boiler, causes an increased surface of water to be presented to the action of the fire, and thus effects an economy in the consumption of fuel; beside which, by causing an interruption to the direct draught of the fire, and thereby turning the flame, the smoke and gas emitted become consumed, and produce a more intense heat than would be otherwise occasioned by the ordinary combustion of the fuel, when the smoke and gas are suffered to escape.

This improvement is stated to be applicable to what is termed Wolfe's boiler, and is represented in section, in Plate V. fig. 3. The patentee does not, however, confine himself in the adaptation of his improvement to this particular sort of boiler alone, nor to the precise form of the additional tube or vessel, as it may be round or oval. The contrivance represented in the figure, at a, is a cylindrical vessel, extending across the furnace and through the brick work, to which water is supplied by the lateral pipes, b, b, issuing from the boiler, and shewn by dots; or it may be injected by means of a pump through the pipe, c; or a column of water, descending from a reservoir, may be made to supply it. The situation of the additional tube, a, in the furnace, is such, that it will stop the progress of the flame, and cause it to descend; by which the smoke and gas are made

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to pass into the fire, and hence become consumed, at the same time increasing the heat of the furnace.

The same contrivance is applicable also to waggonshaped boilers, and may be made to pass under them in a similar manner to that above described. It is also further proposed to contract the fire-place by constructing a case to contain water which shall surround the fire, leaving a small aperture at the lower part of the back communicating with the flues, by which the unconsumed smoke and vapour may pass into the flues and round the boiler as usual. It is particularly observed, that the fuel should not be conducted to the back part of the furnace until its gas is fully consumed.

Inrolled, July, 1821.

To JAMES SMITH, of Hackney, for Improvements in the Machinery employed for Shearing or Cropping Woollen Cloth.

THIS invention purports to be an improvement in the form of the revolving cutters, attached to a certain description of machines employed for shearing or cropping woollen cloths, where the cutters are made to operate by acting as they revolve against the edges of ledger-blades. The improvement is effected by winding several cutting blades round a cylinder parallel to each other, with such an obliquity to the axis that they may each form a suitable shearing angle with the ledger-blades, against which they are intended to be brought, successively, by the rotatory motion given to the cylinder.

Three cutting bars are suggested as the most desirable number to be twisted round a cylinder of two inches

diameter, and three feet long. They are to be so inclined to the axis that one-sixth of the whole length of the bar shall be brought into action in one revolution of the cylinder. In order to form these cutting bars with perfect accuracy, it is proposed that six bars of steel shall be wound round a cylinder, and there operated upon by turning or grinding until they have acquired a truly concentric or circular periphery'; they are then to be removed and hardened. The three bars not intended to be employed may be reserved to supply the place of any one injured by accident.

The patentee states that his "invention consists only in the improved make, form, or structure, of the said cutting bars, and does not embrace or require any alteration in the ledger-blades, or in any other parts of the various machines in use for shearing or cropping. The revolving steel cutters of the improved form may be used as substitutes for the rotatory cutters employed in machines in common use."

Inrolled, October, 1821.

TO ROBERT FORD, of Abingdon-row, Goswell-streetroad, Middlesex, for his Discovery of a chemical Liquid, or Solution of Annotta.

ANNOTTA, or Annatto, (a term derived, we believe, from a Spanish word implying to mark) is obtained from the red pulp which covers the seeds of the Bixa orellana, Roucon or Annatto-tree, a native of South America. Annatto is found in commerce under various forms and names; such as flag annatlo, because brought to this country enveloped in flags; Spanish annatto, which is in

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cylindrical rolls; and occasionally also in the shape of an egg, hence called egg annatto. But the annatto most known to the British public, generally, is a composition of the imported annatto, turmeric, an alkaline salt, and some common colouring earth, such as Venetian red or Spanish brown. It is made up in cakes of about four: ounces each, and is used chiefly by the farmers in the dairy counties for colouring their cheese. The quantity sold annually in England is incredibly great : fortunes of no small amount have been made by the manufacture and sale of cake annatto. The imported annatto is used as a dyeing material for giving orange, or colours bordering on the orange, to various cloths.

The patentee proposes, in order to make twenty gallons of the chemical liquid or solution of annotta, to take about fifty-six pounds of annotta, and reduce it with warm water; then to pass it through a fine sieve, and suffer it to stand at least seven days. To this he then adds the leys of sub-carbonated potash in a "sufficient quantity to produce the colour required;" but states, that other suitable articles may be employed for the same purpose, the quantity and strength being regulated according to the colour intended to be produced, and also according to the quality of the annotta. To the above ingredients are now to be added about six pints of the aqua lixivum caustic, and 192 ounces of alcohol; the whole of which are to be mixed together, keeping it in a closed vessel; and, in conclusion, states, "I farther declare, that as my invention consists in producing a liquid or solution of annatto, (an article I believe to be entirely new,) I shall consider any similar production whether from different articles or variations of quantity of the aforesaid articles, or by what means they are produced, as an infringement on my patent right, as every chemist

must be aware that there are ingredients other than those mentioned above, which may with effect be made to supply their or either of their places."

This is not one of the least extraordinary patents which are from time to time enrolled. In the first place, the kind of annatto is not mentioned; the quantity of water is not mentioned; the quantity of the leys of sub-carbonated potash is not mentioned;—and, by the way, what are the leys of sub-carbonated potash? are they a solution to saturation in water of sub-carbonate of potash? or—but we really do not understand. What, too, is aqua lixivum caustic? (a precious sample this of the patentee's latinity!) We suppose, however, that he means the liquor potassæ of the London Pharmacopoeia, or, in the language of the last century, soap leys. But the great discoverya liquid or solution of annatto-remains to be told. A solution of annatto! Gentle reader, if thou hast ever been so fortunate as to wear those very extraordinary and scarcely heard-of articles, yclept nankin trowsers or pantaloons, and thou wilt make inquiry of any wise and ingenious washerwoman, thou wilt find, to thy no small delight doubtless, that an article called NANKIN DYE (a solution of annatto in water by means of an alkaline salt) has been in common use by their ladyships, the washerwomen, for, at least, one quarter of a century; nay, we are not sure that some of the more grave and learned of that body were not acquainted with it fifty years ago; and, if thou desire to obtain this delectable liquid, we suppose it may be found at almost any oil shop or at the dyer's. However, if thou shouldst demand printed proof of such solutions, we refer thee at once to

Aqua lixivia caustica. Vide Pharm. Edin. 1792.-Does the patentee mean this?