mineral oxyd and precipitate of copper, and thereby producing a permanent pea-green colour, for house and ship painting, and is not liable to decomposition by salt water, which I prepare in the following manner; that is to say: Take fourteen ounces of crude potash, fourteen drachms of crude white arsenic, and boil them in two gallons of soft water, until quite dissolved; then put the liquor into a cast-iron vessel to cool and settle; draw off the liquor clear from the sediment, and put it into a vessel that will hold twenty gallons; add to it six gallons of clear soft water, cold; take one pound of Roman vitriol, and boil it in two gallons of soft water till dissolved; put the solution into an open vessel till quite cold, then to be added gradually to the aforesaid solution of fixed alkali, stirring it well all the time, which will produce a genuine green oxyd, then to proceed in the usual way of mineral green. A most essential part of this preparation is to make the mineral green without using caustic alkali, which is the general way of manufacturing it for this pose the caustic alkali acts so powerfully on the vegetable quality of linseed oil used in this preparation, and thereby rendering it mucilaginous.

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Preparation of precipitate of copper to mix with the aforesaid oxyd; viz. take one pound of Roman vitriol, and boil it till dissolved in two gallons of soft water, at the same time dissolve in another vessel half a pound of the first soft American pearlash; put the solution of vitriol, boiling hot, into a vessel that will hold ten or twelve gallons; then add to it gradually the solution of pearlash, boiling hot; to be well stirred all the time. On mixing the solution together it will cause a strong effervescence; if the pearlash is good it will be enough to precipitate the vitriol, which will be known by the effervescence immediately subsiding, and the precipitate failing to the

bottom

bottom of the vessel, and thereby producing a fine green colour: when settled draw off the clear liquor; then put it into bags, made of canvas, to filter, and when well drained to be laid on chalk stones, to draw a further quantity from it; then to be put into a stove to dry.

Preparation of mixing or combining with mineral substances in linseed oil: Take one pound of the genuine mineral green, prepared as herein described, to be well powdered; one pound of the precipitate of copper, one pound and a half of refiners' blue verditta, three pounds of white lead dry powdered, three ounces of sugar of lead, powdered fine; the whole of these ingredients to be mixed up in linseed oil, and ground in a levigating mill, passing it through until quite fine: it will thereby produce a bright mineral pea-green paint, will preserve a blue tint, will keep any length of time, in any climate, without injury, by putting oil or water over it.

Directions for using the said colour for house or ship painting: Take one pound of the green colour paint, prepared as aforesaid, with one gili of pale boiled oil; mix them well together; this will produce a strong peagreen paint: the tint may be varied at pleasure, by adding a further quantity of white lead, ground in linseed oil. This colour will stand the weather, and resist salt water; it may also be used for flatting rooms, by adding three pounds of white lead, ground in half linseed oil and half turpentine, to one pound of the green; then to be mixed up in turpentine spirits, fit for use. It may also be used for painting Venetian window-blinds, by adding to one pound of the green paint ten ounces of white' lead, ground in turpentine; then to be mixed up with turpentine varnish for use. In all the aforesaid preparations it will retain a blue tint, which is very desirable. VOL. XXV.-SECOND SERIES. When

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When used for blinds a small quantity of Dutch pink may be put to the white lead if the colour is required of a yellow cast.

In witness whereof, &c.

Specification of the Patent granted to JOHN HANBURY the Elder, of Bartlet's Buildings, in the City of London, Carpet-manufacturer; for a Method of weaving Carpets, commonly called Scotch or Kidderminster, by which a new and finer Texture, and larger Patterns, can be produced than by any other Method hitherto known.

Dated December 19, 1813.

To all to whom these presents shall come, &c. . Now KNOW YE, that in compliance with the said proviso, I the said John Hanbury the elder do hereby declare that the nature of my said invention consists in a new method of weaving or manufacturing of carpets and carpeting, thereby producing an article or manufacture which I call flush carpets or carpeting; the method of weaving or manufacturing which said flush carpets or carpeting is hereinafter described, viz. After I have prepared a loom, in the same manner as is usual for weaving or manufacturing Scotch or Kidderminster carpeting in one thread, or two threads, or more, I proceed as follows: For a plain ground and ribbed figure; First, when I have woven as many shutes as I choose to make the rib, I raise up the contrary lash to that of which I form the figure, and the same ground plain which I had up when I wove the last ground shute; by the word plain throughout these several descriptions, I mean a fourth part of the warp or chain, which warp or chain consists of two coloured and two ground plaius. Then I throw a shute, which I call the binding shute, which may con

sist of thread or threads, of woollen, worsted, linen, cotton, silk, hair, wire, or any other material that will produce the same effect, or raise up one ground plain or two ground plains, and throw in the binding shute or raise up the ground and half the colours in the ground, and half ground in the figure.

Ribbed, ground, and plain Figure.

Second. When I have thrown as many shutes as I chuse to make the rib, I raise up one coloured plain or two coloured plains, or draw up the contrary lash to that of which I form the figure, and the coloured plain also, then throw in the binding shute as above.

Both ground and figure ribbed.

Third. When I have thrown sufficient shutes for the rib, then raise up one half of the chain or warp, and throw in a binding shute; then draw up the other half, and throw in another binding shute, or raise up the contrary lash to that with which I form the figure, and throw in a binding shute, or raise up the lash and one plain, throw in one binding shute, and keep up the same lash, and raise up another plain, and throw in another binding shute.

Ground and figure plain on both Sides.

Fourth. When I have thrown in as many shutes as I may want or choose, I raise up the ground plain and coloured plain I had up when I wove the last two shutes, and throw in the binding shute, or three plains in the ground and two in the figure will produce the same effect, or the webs may be united with one of the shutes that form the figure, by raising up half the ground and half colours in the ground, when I throw the coloured shute with which I bind them together.

General Directions.

First. In producing any of the foregoing articles a tail cord, or tail cords, may be dropped occasionally, but the article in that case will not be so perfect as it is without dropping a tail cord, or tail cords.

Second. In any instance where I have to draw up the contrary lashes, I should prefer an additional engine beam and box for that purpose; and when I produce the article with rising up plains only, I should prefer additional treadles, according to the number of plains I have to rise, except when black-up loom, on draft loom, or open shade loom, is used, in which case extra treadles will not be necessary for the plains. But in case of having an extra engine in the black-up loom, one enginetreadle additional will be necessary.

In witness whereof, &c.

On the Construction of Roads.

By RICHARD LOVELL EDGEWORTH, Esq. F. R. S. M. R. I. A. and Civil Engineer.

With an Engraving.

From his ESSAY on the CONSTRUCTION of ROADS and

CARRIAGES.

Pavement.

STONES in a common pavement are usually somewhat oval, from five to seven inches long, and from four to six inches broad. They are laid in parallel rows on the road, Fig. 1, (Plate IV.) or alternately, Fig. 2, as bricks are laid in a wall.

On the pavement, Fig. 1, wheels slip from the round tops of the stones into the joints between, and soon wear away

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