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forms of parts herein shewn, nor to the materials of which the same is to be composed, but he claims, Firstly,—the peculiar arrangement of apparatus, herein shewn and described, or any modification thereof. Secondly,-any apparatus for regulating the flow of air or gas, in which such regulation is effected, by means of a conical plug, or the conical end of a tube, either hollow or solid, rising into the aperture through which the gas passes, and thereby closing, or partially closing, the same, and preventing the air or gas from passing, as above described.—[Inrolled in the Rolls Chapel Office, August, 1842.]

Specification drawn by Messrs. Newton and Son.

TO HENRY BEAUMONT LEESON, of Greenwich, M. D., for improvements in the art of depositing and manufacturing metals and metal articles, by electro-galvanic agency, and in the apparatus connected therewith.-[Scaled 1st June, 1842.]

THE first improvement consists in a new method of arranging and constructing a galvanic battery, in order that the intensity and quantitative effect of the galvanic current may be easily regulated.

In Plate XIII., fig. 1, is a longitudinal section of the battery; and fig. 2, is a plan view of the frame to which the metal plates are attached. a, is a rectangular wooden trough, containing a wooden frame b, formed with vertical. grooves in its sides, to receive a series of porous cells c, c, c. The plates of the battery are suspended in the fluid or fluids by brass forks d, d, fastened to a wooden frame e, e, which rests upon the trough a, and is connected to the other frame b, by two pins f, when they are required to be raised together out of the trough a, a.

The battery may be charged, as usual, with one or two fluids; one of them, in the latter case, being contained in the porous cells c, c, c; and plates of copper and zinc, or any other suitable metals, may be employed.

The second improvement consists in cleaning copper and

zinc plates, (after they have been used in a battery or batteries,) by the employment of a galvanic battery; and also in amalgamating, or coating with mercury, the surfaces of zinc plates, by the same means, to render them suitable for being used in the construction of galvanic batteries.

The third improvement consists in the employment of certain electrolytic fluids, for the purpose of exciting an electric current, to be used in the deposition of metals. These electrolytic fluids are produced by combining nitric, muriatic, or sulphuric acid with any of the following solutions or substances, viz:-impure ammoniacal liquor, as obtained from the gas works; lime liquor, after it has been used for purifying coal gas; impure alkaline sulphurets of potassium and sodium, produced from the sulphates of potash and soda, by calcination, in a furnace, with coal and chalk, or charcoal; sulphurets of calcium, barium, and strontium, produced from the sulphates of lime, baryta, and strontia; ammonia, potash, and soda, and their carbonates; and, lastly, the acid solution of sulphate of iron, (obtained by the decomposition of iron pyrites, in the manufacture of green copperas,) which is to be used with any of the lastmentioned alkaline solutions or sulphurets.

The fourth improvement consists in the application of what the patentee terms an "intensity arrangement," for depositing metal from solutions; whether the metal originally formed part of the solution, or became such by the action of some electrolytic solution upon a cathode, formed of the metal required to be deposited. The intensity arrangement or battery is constructed in the manner represented at fig. 1, and consists of from 18 to 90 pairs of plates; but a still greater number of plates may be employed, if required.

The fifth improvement is divided into three parts:-the first part consists in using an elastic mould, for obtaining casts in wax, stearine, tallow, and other similar snbstances; which casts are afterwards made conductors of electricity, and metal is deposited upon them. The mould is produced by applying to the article, which is to be copied, four or five coats of a solution of glue, about the consistence of

treacle; it is then surrounded with a strip of thin metal, cartridge paper, or other material, at such a distance as will admit of a quantity of the solution being poured in, so as to give the mould sufficient strength, when cold. A solution of caoutchouc, and other gums and resinous substances, may be added to the glue; or a "leathery consistence" may be given to it, by the application of a solution of tannin. After standing from five to ten hours, the mould is removed from the article, and is ready to be used in forming casts.

The second part consists in manufacturing articles in silver, by depositing that metal upon moulds of wax, plaster of Paris, and other non-conducting surfaces, using, for that purpose, the intensity arrangement, and a strong solution of cyanide of silver and potassium; the solution is formed by dissolving from ten to twenty ounces of the pure salt in one gallon of distilled water, and then adding one ounce of cyanide of potassium.

The third part consists in methods of ensuring a smooth deposit of metal upon uneven surfaces. For this purpose, a pin or wire is attached to those parts which project much beyond the rest of the surface, in order that it may receive the rough deposit; after the operation is completed, the pin is cut off. When two portions of an article face each other, or are much undercut, the patentee connects wires, or other surfaces, of the same metal as that to be deposited, with the anode of the battery, and bends them into the space between the two parts. The deposition of metal on wax, or other non-conducting substances, may be facilitated by inserting conducting wires into the mould or model, so as to cause the deposit to take place on many points at once; and the cathode, or supply metal, should be so shaped, as to enclose the article at nearly an equal distance from every part of it.

The sixth improvement consists in obtaining a smooth external surface, and causing a greater amount of metal to be deposited in a given time, by communicating motion to the anode, or object to be deposited upon, (taking care that it does not revolve on its own axis,) or to the solution in which it is immersed.

The seventh improvement consists in forming the reflecting surfaces of parabolic and other reflectors and specula by electro-deposition. A mould is made of the required form, and upon it a sufficient thickness of silver, antimony, or other metal, or metallic alloy, is deposited; the front surface of it is then polished, and it is strengthened by depositing copper upon the back.

The eighth improvement relates to various methods of depositing metallic alloys:-the first method consists in connecting the anode, or article to be covered, to the terminal cathodes of as many batteries as there are different metals contained in the alloy, and immersing it in a solution, composed of similar salts of the different metals; this solution also contains a cathode plate of each of the metals composing the alloy, and each plate is connected to the anode of one of the batteries.

The second mode consists in the employment of one battery, with the "alternating cathode" represented at fig. 3. It consists of a beam a, mounted on the shaft b, which turns in bearings, carried by standards c; the beam communicates with the anode of the battery by the wire d, and a vibrating movement is given to it by the rod e, from the shaft f, which is driven by an electro-magnetic engine, or any other suitable prime-mover. g, g, are two vessels, containing mercury, connected by wires h, h, with the cathode plates of the two metals composing the alloy (but if the alloy is to consist of more than two metals, then more vessels g, will be required, one for each cathode plate); these plates are immersed in a solution, composed of similar salts of the different metals to be deposited, together with the anode, or surface to be deposited upon, which is connected by a wire with the cathode of the battery. A communication is established between the two cathode plates, or supply metals, and the anode of the battery, by means of the rods i, i, which are caused, by the vibration of the beam a, to dip, alternately, into either one or the other of the vessels g; and thus, each metal will be deposited on the article to be coated during the time that the connection is established between it and the battery, by the immersion

of its rod in the vessel of mercury. The relative proportions of the two metals is adjusted by lengthening or shortening the rods i, i, as shewn in the drawings; so that they may be immersed for a longer or shorter period in the mercury.

A modification of the first method of depositing alloys consists in using two or more batteries, with an alternating cathode, by which they are brought into action alternately. Another mode consists in employing a mixed solution, as before, and connecting a cathode plate of each of the metals forming the alloy to the anode of the battery; but this the patentee does not recommend.

The last method consists in the use of any of the nonmetallic electrolytic fluids to be described under the eleventh improvement, in combination with any of the above-mentioned arrangements.

The ninth improvement consists in preparing metallic surfaces for electro-deposition, by covering the same with a slight coating of metallic mercury, in order to produce greater adhesion of the metal afterwards deposited upon them, and a "deader" effect on the surface. It consists in dipping the article, after it has been properly cleaned, into a solution of a compound of mercury in water; by preference, a solution of cyanide of potash and mercury. By this means, a slight coating of metallic mercury is obtained upon articles of copper, and its alloys, zinc, and some other metals; and the article is afterwards placed in the electrolyte, and undergoes the process of electrodeposition.

The tenth improvement consists in arranging the articles, which are to be covered with metal, in a battery, so as to assist in generating and maintaining the galvanic current. The articles are disposed in a series, forming the anodes of the arrangement, and the cathodes are formed of the metal to be deposited; but zinc, or other oxidizable metal, may be employed.

The eleventh improvement consists in depositing gold, silver, platinum, lead, zinc, tin, nickel, cobalt, and mercury, by the aid of electrolytic solutions not originally containing

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