From the above description, it will be understood, that the spring is to be fastened at one end only, the rest of the spring being allowed some play between the in and outersoles; it being one essential feature of the invention, that the spring should be fixed only at one end, so that the play, between the soles, above described, may freely take place. Instead of fastening the spring at the heel part of the boot, as shewn in the drawing, and above described, it may be fastened at the opposite end, to the sole, and allowed to enter and work in the heel; or it may be fastened at the middle to the waist of the boot, each end of the spring being free; but the method shewn in the drawing, at fig. 1, is preferred.

The patentee claims the improvements in the manufacture of boots and shoes, by the use and application of metallic springs, as above described.—[Inrolled in the Petty Bag Office, October, 1843.]

Specification drawn by Messrs. Newton and Son.

To CLAUDE SCHROTH, of Leicester-square, in the county of Middlesex, Gent., for certain improvements in the process, manner, or method of embossing or producing raised figures, designs, or patterns, on leather, or such like materials; and in the manner or means used for effecting the same; also in the making or forming of certain tools or apparatus used therein.-[Sealed 26th June, 1839.]

THE object of this invention is to produce, in an economical and perfect manner, fac-simile copies of designs, figures, or patterns, done in basso-relievo or raised figures, whether stamped, carved, embossed, sculptured, modelled, cast, or otherwise produced; such copies or fac-similes being obtained in leather, or the skins of animals, and in connection with other materials, when required. These copies of devices are applicable to all the purposes for which bassorelievo ornamental work is employed; viz., for the decoration of the interiors or exteriors of buildings, (as medal

lions, cornices, panels, rosettes, picture or other frames, &c. &c.,) and for cabinet-work, and various other articles of furniture.

- The invention consists in an improved process or method of producing such fac-simile copies, in basso-relievo or raised ornamental articles, and in making or forming the dies, or apparatus, used in the process of obtaining the same.

The metal blocks, plates, moulds, or dies, to be used in producing the copies or fac-similes of the different bassorelievos, are made by casting them from plaster or clay models, which are prepared for this purpose, either by taking impressions, or moulds, from old carvings, embossing, pieces of sculpture, or castings, or by modelling or forming new patterns, designs, or figures, in clay or plaster materials, in the same manner as sculptors model their designs, previous to operating upon marble. The dies are formed of any suitable metal, or mixtures of metal, but the patentee prefers the following alloys:-1st, lead and antimony, in about the same proportions as used for typography. 2nd, fusible alloy of bismuth, lead, and tin, (as that commonly known as Darcet's alloy.) The propor tions are varied, according to the use intended to be made of the dies.

The alloy of lead and antimony is used for those dies in which the skins are to be embossed, without using the press, as hereafter explained; and the alloy of bismuth, tin, and lead, for the dies that are submitted to the action of the press.

The dies, into which the leather or skin is forced by hand, require to be only about the thickness of threeeighths of an inch; this thickness being regulated by the process of making them.

The plaster, clay, or other model or design, being prepared, a thin sheet of tin, pewter, tin-foil, or lead, is laid over it, and caused to take the form of the design (i. e., made to enter into all the counter-sunk parts and interstices); then upon the sheet of tin-foil is placed a layer of earthy materials, of the same thickness as the die or block

is intended to be cast. Over this earthy covering, plaster of Paris, mixed with water, is poured, in order to form a recipient for the metal alloy; the object of this recipient being to economise the alloy. When the plaster becomes set, the cap, or tin-foil, is raised, and the earthy matters are removed.

It will be understood, that on the model being placed in the hollow plaster recipient, the projecting parts of the model will correspond with the counter-sunk parts of the recipient, and between the model and recipient there will be a space, equal to the thickness of the earth used in the first operation. The recipient is now placed on the bed of a screw-press, and properly adjusted, and the requisite quantity of the alloy, in a fluid state, poured into it The alloy is stirred by the operator (to prevent the heavier metal separating from the lighter) until it arrives at a proper consistence; and then the plaster model being carefully placed upon it, the follower of the press is brought down quickly, forcing the model into the alloy, and thus producing the required matrix or mould. When great nicety is requisite in obtaining the matrix, the model should be accurately adjusted, and fixed to the follower of the press.

In order to prevent the model from breaking, by being too suddenly brought into contact with the hot metal, it should be placed in a stove or oven, to drive off any moisture it might contain, and then allowed to cool in a dry place. If the same model is required to be used several times, it should be made of lead, or any other suitable substance, instead of being formed of plaster.

The blocks, plates, moulds, or dies, which are intended to bear the action of frequent pressure, or many operations, should have their undersides plane and smooth, in order that every part may sustain an equal pressure. Such dies are obtained in the manner first described; but instead of casting them in plaster recipients, they are made in one piece, in boxes, formed of any suitable substance which is a bad conductor of heat, such as wood, pasteboard, &c. These boxes should exceed in length and width the dimensions of the model, and the height of their sides should

exceed, in a small degree, the thickness of the metallic casting.

The method of manufacturing embossed leather ornaments, consists in forcing such leather into all the countersunk interstices of the block, plate, mould, or die, and is effected as follows:-The skin is first beaten in water, until it becomes completely softened and thickened, and then the operator takes it out of the water, and, without wringing or pressing, rolls and works it with his hands, so as to make it shrink, that is, to increase its thickness at the expense of its width and length, after the manner of fulling. He then places it in the middle of the metal mould, and having ascertained the centre part of the design, he proceeds, by gently unrolling the edges of the skin; and then, with the ends of his fingers, begins the operation of pressing the skin into the interstices of the die or plate, and stretching out the leather, proceeding gradually from the centre of the plate to the outsides; for it is at the expense of the width and length of the skin that the cavities of the mould are filled.

When the principal cavities are sufficiently covered or filled with leather or skin, the workman proceeds to fill up the smaller cavities, by means of a wooden, bone, or copper instrument; (similar to those used by sculptors, for modelling,) sometimes making use of a brush, with which he gently strikes the skin. He then presses on the surface of the leather a sponge, which has the double effect of compressing the leather into the more minute cavities of the design or mould, and at the same time absorbing the greater portion of the water which the skin had taken up. At this stage of the proceeding, either of the following methods may be employed to complete the embossing and drying of the leather; viz., it may be effected by means of heat, or by the agency of an absorbing substance.

In order to dry and finish the articles by heat, the mould or die, containing the skins, is to be placed on a chafingdish, until the temperature reaches from about 1080 to 144° Fahr. During the drying operation, papier-maché, or other suitable material, previously prepared, is forced

into the deepest cavities of the skin or leather, in order to keep it in its place, and prevent it receding from the die,— the preparing tools, and sponge, being constantly pressed on all the parts, and in different directions, in order to cause the leather to adhere to the cavities of the mould, until it and the papier-maché are dry.

The papier-maché, with which the cavities are filled, may then be removed, and the operation is finished. The elasticity of the leather, and its contraction, in drying, allows of its being drawn out of those parts of the mould which otherwise would retain it, and consequently the mould need not be made of several pieces.

The second method of compressing and drying, consists, as before stated, in the employment of an absorbing substance. The substance used for this purpose must be reduced into fine powder, or very minutely divided; and the patentee prefers those materials whose particles are sufficiently void of cohesive properties, as to remain in a state of division, after being strongly and repeatedly pressed.

The mould, after it has received the leather or skin from the hands and tools of the workman, as above described, is placed on the table or bed of the press, and is enclosed in a frame of wood or metal, formed of side-pieces, without top or bottom; the top edges of the frame being about two or three inches higher than the mould, when the design is not much in relief, and from about six to twelve inches, or more, when the embossing is raised in a greater degree.

The frame is to be filled with fine saw-dust of wood, well dried, or dust of other suitable material; so that the die or mould may be covered with a layer of such dust. Above the frame is placed a plate, or follower, of such a size as will enter freely within it. The screw of the press being turned, compression takes place, and the saw-dust forces the leather into all the cavities of the mould. After a short time, the screw may be turned in a contrary direction, and the frame and saw-dust removed; the leather having acquired a sufficient consistency to be drawn out of the mould, and dried by heat, or in the open air, according to circumstances.