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Harford's, for Improvements in Puddling.

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In consequence of these discoveries he has been induced to investigate the nature and properties of such other materials as appeared suitable for the purpose, and has found out certain substances which will completely prevent the bad effects above mentioned in the employment of slag, scoria, or sand. He has also observed when the cast iron bottoms, or floors, of puddling furnaces are covered with sand, slag, or scoria, that portions of the siliceous matter, contained in these substances, become intimately united and intermixed with the iron which is undergoing the process of puddling, and, of consequence, a great portion of these impurities are imparted, and the iron rendered very inferior in quality to iron which has been operated upon by the improved process.

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In order to prevent the inconvenience above described, the cast iron bottoms of the puddling Furnaces are to be spread over with a quantity of charcoal, either in the state in which it is obtained from the manufacturer, or reduced to powder, the latter of which is preferred: for," as the charcoal in either state is a non-conductor of heat, it answers the purpose of protecting the cast iron bottoms, or floors, from the injurious effects of intense heat better than any substance, or material, hitherto used for the preservation of cast iron bottoms or floors."

Although the Patentee prefers to employ charcoal in the way above described, yet the same beneficial effects may be obtained by using chips or shavings of wood, saw-dust, peat-turf, the spent bark from tan-pits, plumbago, old leather, leather shavings, soot, and many other animal and vegetable substances, from which, when heat is applied, a sufficiently durable charcoal may be obtained for the above purpose.

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The specification concludes by saying, "I do hereby

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further declare, that my said invention consists in not only having discovered the benefit of using various substances for the better preservation of the cast iron bottoms and floors of puddling furnaces, but for the substitution of such substances for those of slag, scoria, or sand, which impart, and engender impurities very injurious to the formation of good iron; but which my invention totally obviates, and thereby produces a superior iron, and thus effects an important improvement in that department of the manufacture of iron commonly called puddling."

On a perusal of the specification of this patent we cannot avoid observing the manifest advantages which are to be obtained by a knowledge and careful application of the principles of chemistry to the useful arts. Prima facie, no person unacquainted with chemical principles would have taken powdered charcoal for the purposes to which it is applied in this specification: we cannot therefore too much press upon the attention of every one devoted to the arts, the great utility of chemical knowledge, and the necessity of its study to form a proficient artist.

Inrolled, May, 1822.

TO RICHARD MACNAMARA, Esq. of Canterbury Buildings, Lambeth, Surrey, for the Invention of an Improvement in Paving, Pitching, and Covering Streets, Roads, and other Places.

THE patentee states that he has observed much difficulty and repeated failures take place in attempts made to render the present mode of paving streets and roads permanent for any reasonable length of time; this he considers to arise from the unconnected manner in which

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the ordinary paving stones are placed. He has also observed, that it frequently happens one or more stones sink partially when great weights pass over them; the consequence of this is, an accumulation of water takes place in those hollows, which ultimately loosens the foundation of all the surrounding stones, and so much injures the road as to cause a continual expense in reparation.

The improvements proposed, consist in forming the sides of the paving stones with such angles to their horizontal surfaces as shall enable them mutually to support each other, and thereby prevent the liability of one or more stones sinking partially, and producing hollows in the road, which improvement will obviate the evil consequences above-mentioned, and preserve the road in a sound and level state, for a long time, without reparation.

Plate III. fig. 8, represents the upper surface of a portion of paving about eight feet square, composed of twelve blocks of stone placed in contact, the edges of which are bevelled at angles alternately, acute or obtuse to the plane of the upper surface. Fig. 9, is an edge view of several blocks in which the bevels of the sides of the blocks are shewn. The object of thus forming the contrary edges of the blocks at contrary inclinations, is that the two obtuse sides, à, a, of each block, as B and D, shall be made to support the acute sides, b, b, of the blocks, A and C, adjoining, or in lateral contact; while the transverse ends of the blocks, B and D, being acuté, will rest upon, and be supported by the obtuse sides of the blocks placed behind and before them. Thus it will be seen, that, by cutting the transverse edges of the blocks as above directed, the whole mass of paving will lock together, and each block mutually support those placed next to it.

These blocks may be made of any convenient size, as this particular form of the block will equally apply to any dimensions; the principal object to be attended to is, to make the boundary lines on the upper surface at right angles, and to keep the faces of the bevelled sides as perfect as the nature of the stone will permit. When blocks of large dimensions are employed for paving stones, it will be proper to cut grooves at certain distances upon their upper surfaces, corresponding in shape and size to the division between ordinary paving stones, for the purpose of affording a secure foot-hold to the horses in travelling over them.

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There can be no doubt that the adoption of the method proposed by the patentee will obviate, in some degree at least, the present inconveniences attendant on paved roads; but we fear the expense of hewing the stones to the shape will be an insuperable bar to its introduction. A still further improvement in the pavement of the streets of London, and other towns, would, perhaps, be to form them in a segment of a circle, and let each stone be a part of an arch; this would remove much of the pressure from the substratum to the sides. But the expense, in this case, would be of course great. Inrolled, May, 1822.

TO JAMES WINTER, of Stoke-under-Hamdon, in the County of Somerset, for certain Improvements in a Machine for Sewing and Pointing Leather Gloves with Neatness and Strength, much superior to that which is effected by Manual Labour.

THIS invention is an improvement upon a former machine for sewing and pointing leather gloves, for

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Winter's, for Sewing Leather Gloves.

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which a patent was granted to the same person in 1807. Plate I. fig. 4, represents a pedestal, upon which the instrument, called the jaws, is to be placed. Fig. 5, shews the jaws, which instead of opening and closing by a circular movement upon a joint, as described in the former specification, are now made to open and shut by a parallel, horizontal movement, effected by a slider and screw; a, a, is the fixed jaw, made of one piece, on the under side of which is a tenon to be inserted into the top of the pedestal. By means of this tenon the jaws may be readily displaced, and another similar pair of jaws placed in their stead, which affords the advantage of expediting the operation by enabling one person to prepare the work whilst another is sewing; b, b, is the moveable jaw, made of one piece. The two jaws being placed together in the manner shewn at fig. 5, the moveable jaw traverses backwards and forwards upon two guide-bars, c, which are made to pass through holes exactly fitted to them in the lower parts of the jaws. At the upper part of the jaws are, what are called, the indexes, d, d, which are pressed tightly together by a spring, shewn at fig. 6, and intended to be introduced between the perpendicular ribs of the jaws at e. At f, is a thumb-screw passing through the ribs for the purpose of tightening the jaws, and holding the leather fast between the indexes while being sewn; this screw, however, will seldom, if ever, be necessary if the spring is sufficiently strong; g, is an eye or ring fixed to the moveable jaw, through which the end of a lever, h, passes; this lever is connected by a spring to a treadle, i, at the base of the pedestal, and by the pressure of the right foot upon this treadle, the moveable jaw is withdrawn, so that the person employed in sewing may shift the leather, and place another part of the glove be

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