portable diving bells of India rubber, or air and waterproof cloth or fabric protected by skeleton framing, formed of metal or other material, is shown in figs. 15, and 16. Fig. 15, is a side view of one of these diving bells, and fig. 16, is a vertical section of the same: a, a, a, is the metallic skeleton framing; b, b, the air and waterproof cloth; c, c, are the glasses, properly secured in the cloth, to admit the light and allow the divers to look out; d, d, are the chains or ropes by which the bell is suspended; the seats for the diver being formed by ropes suspended from the top part. The weights necessary to cause the bell to descend may be of iron, lead, or stone, as most convenient or at hand, and should be fastened round the bottom part of the framework at e; g, g, is the supply pipe for the fresh air, which is connected to the pipe h, h, extending round the inside of the bell, and has a number of small holes pierced in it, through which the air escapes into the bell; the exit and foul air is taken off by the pipe i, i, one end of which is open to the interior of the bell at the top, and the other end is open for the escape of the exit air below. The lower end of the pipe i, should always be a little above the bottom part of the bell, in order that the air may escape easier by the pipe than under the sides of the bell. If it should be thought desirable, the bell may be further protected and strengthened by a gauze or net-work of wire or cords placed within the metal framing; or the framing itself may be formed of wire net-work, in segments, to render it portable, so as to be put together when wanted; and, if desirable, the bells may be furnished with air bags to be filled by the divers, in order to allow of their being carried about by them, such bags being furnished with pipes passing through the air and waterproof cloth by an air and

water-tight connexion, and having stop valves on their ends. The bags are also furnished with valves at the top, to allow the air to escape when requisite. In fig. 16, is represented a section of one of these air bags:" k, is the bag; 7, the pipe by which the bag is filled with air by the diver in the bell; m, the stop valve at the end of the pipe; n, the top or escape valve, which is opened by the diver pulling the wire o, placed in the valve'm m, and thereby pulling the cord p, which is attached to the wire o, and tail of the valve n. The framing should be fastened together by screw nuts and bolts, so that it may be readily taken to pieces when required.

The object of my seventh improvement is, to obtain a more constant or continuous stream of air from a single-action force pump, than can be obtained by those of the common construction, and is shown in the vertical section of the pump at fig. 18: a, is the cylinder of an ordinary single acting pump; b, the piston, working in the cylinder and connected to the rod c, which is attached to the lever d, having its fulcrum on any part of the framework of the pump; e, is the valve to admit✨ the air into the cylinder; and f, is the foot or exit valve. This pump is worked by forcing up and down the lever d, precisely in the way of working common singleaction pumps, my improvement being the application of the air, regulating chamber and apparatus, which I shall now describe:

"The air, as it is forced from the cylinder a, at every down stroke of the piston, passes through the foot valve f, along the passage g, into the chamber h. This chamber is furnished with an air-tight flexible bag or diaphragm i, securely fixed, air-tight, round its edges at the flanges k, and divides the lower part of the chamber h, from the upper part l. Previous to working the pump,'

the upper part of the chamber, contains air of the com mon atmospheric pressure, or of a greater density if required; but when the pump is set to work, and the diver is descending, the air in the chamber h, increases in density, and the air in the upper part of the chamber 1, becomes compressed, the flexible diaphragm giving. way to the pressure of the infected air; and, as at each) up stroke of the piston, there is a cessation of the injec-. tion of air from the pump into the chamber h, at this, time the elastic force of the compressed air in the upper part of the chamber at 1, acts upon the flexible diaph‐{ ragm, and, expanding in volume, expels the air from. the lower part h, until the next down-stroke of the piston, when a re-action takes place. By these means,.. the elastic force of the compressed air above the diaph ragm acts alternately upon that below, and thereby keeps up a more continuous stream than can be ob-: tained by a single-action pump of the ordinary con struction.

,M

"My eighth improvement, viz. the application of hydraulic engines to raise heavy weights or wrecks of › sunken ships or vessels, or drawing up piles from under water, is shown in fig. 19: A, A, represents sections of two buoyant vessels properly strengthened internally by timbers; B, represents a wreck of a ship or sunken vessel; c, c, are the cylinders of two hydraulic engines, in which water is forced by pumps in the manner of the common hydraulic press, the expansive force of the compressed water being exerted upon a piston attached to the rods and cross heads D, D, moving in parallel guides F, F; to these cross heads, strong chains G, G, are attached, which are passed through tubes, truuks, or pipes H, H, the lower ends of which protrude through the bottom of the vessel, and are open to the water:

the chains G, G, are attached to other chains I, 1, passed round the wreck or other heavy weight. These chains may be further secured and fastened by a number of screw bolts to the vessel; there are stoppers at K, K, which are made to take hold of the chains as soon as the piston has arrived at the top of its up-stroke, and retain them while the pistons and cross heads are descending to take hold of a fresh length of chain; which operation is repeated until the weight is brought to the required height; by these means, the wreck or other heavy weight may be raised up to the buoyant vessels, when they may be floated or towed into harbour or shallow water. It will be evident that the same power may be applied to draw up piles, or remove other obstructions. And, I would here remark, that I propose to assist the raising such vessels and wrecks by screwing into their sides, screw bolts with ring-heads, such as represented in fig. 20; and to attach to such bolts, airproof bags, casks, or cases of metal or wood, by hooks fastened to them, which bags, casks, or cases are to be filled with the exit air from the diver's helmet; but such air-proof bags, casks, or cases are well known, and form no part of my invention.

"My ninth and last improvement, viz. in the method of surveying and inspecting from above, objects which are beneath the surface of the water, consists in illuminating the bottom or bed of the sea, or the wreck of a vessel or particular spot, by reflectors directing the sun's rays, or by sunken lamps or lights, in the manner hereinbefore described, and in inspecting and surveying from above, the bed of the sea or the objects so illuminated through open tubes or trunks, partly immersed in water, to prevent the ripple on the surface interfering with the sight; into which tubes or trunks, telescopes

of the ordinary construction, may be placed: by these means the party surveying will be better able to distinguish from above, objects below the surface of the water. Fig. 21, represent surveyors at work in a boat: a, is the light lowered by the rope b, on to the bottom or bed of the sea; c, is the air supply pipe; d, the tube partly immersed in water to prevent the ripple of the surface interrupting the view, and into which the surveyor places his telescope, or when used without a telescope, the top of this tube should be furnished with a hood fitting the face, to exclude the glare of light." [Inrolled in the Rolls Chapel Office, July, 1835.] Specification drawn by the Patentee.

TO FREDERICK BURT ZINCKE, the younger, of Crawfordstreet, Marylebone, in the county of Middlesex, Esq., for his invention of the preparing or manufacturing of the leaf of a certain plant so as to produce a fibrous substance not hitherto used in manufactures, and its application to various useful purposes.-[Sealed 9th December, - 1836.]

THIS invention relates to preparing the fibrous parts of the leaf of the pine-apple plant, and rendering the same applicable to the various purposes for which hemp, flax, tow, cotton, and other fibrous substances are now used.

The invention is stated to consist, first, in operating upon and preparing the leaf of the plant so as to separate the fibrous parts thereof from the cuticle pabulum, or other matters of which the leaves are composed; and the application of the fibres so prepared to the making of linens, cambrics, shawls, and other woven fabrics or piece goods; and also to the making of ropes, cordage, string, thread, paper, &c.