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THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



[September, 



massicot of commerce, to the vapours of vinegar ami carbonic acid gas. Or, 

 third, he exposes a solution of acetate of lead, or other suitable salt of lead, 

 made from " the oxide obtained as aforesaid," to an atmosphere of carbonic 

 acid gas. We quote at length the patentee's description of the mode in 

 which this is effected ; it is new, ingenious, and likely to answer well. " In 

 chambers, or large jars of earthenware, or other material, are suspended 

 several large sponges, which are supported in the jars by strings of worsted, 

 so as not to touch the sides of the jar, or one another. Having made a 

 saturated, filtered, and neutral solution of acetate of lead, or of other suit- 

 able salt of lead, from the oxide obtained as aforesaid, and placed this 

 solution in a vessel above the top of the jars, and having moistened slightly 

 the sponges with the solution, and also the worsted strings suspending 

 them, the strings are then made to dip into the solution contained in the 

 vessel above the jars, and, by the power of capillary attraction, the sponges 

 are kept constantly moist by a supply of the solution descending down the 

 worsted strings j and the supply can be regulated at pleasure by the size of 

 the strings, or otherwise. Evaporation is continually going on, and crops of 

 salts of lead are formed on the surface of the sponges. The jars are made 

 to communicate with a gas-holder, or other reservoir, containing carbonic 

 acid gas, which gas is made to fill the jars in order that the sponges may be 

 surrounded with an atmosphere of carbonic acid gas. By the action of the 

 gas, the salt of lead on the sponges is readily converted into ceruse, assisted 

 probably by the decomposition of the acid of the original solution. When it 

 has been ascertained that a sufficient quantity of the ceruse has been formed, 

 the sponges are removed and washed in a vessel of pure water ; and if the 

 sponges contain any undecomposed soluble salt of lead, which is generally 

 the case, the water dissolves it, but the ceruse falls to the bottom on the 

 water remaining at rest. The water is to be re-used for forming the solution 

 when decanted from the precipitated ceruse. The sponges are then replaced 

 as before and the .process continues." Fourth, he employs common soot to 

 deoxidize his oxide of lead, and generally for the reduction of all metals from 

 their ores or oxide. Fifth, when a mass of melted lead, treated by the pro- 

 cess just described, contains any silver, the silver, being less oxidizablc than 

 the lead, accumulates at the bottom of the pot, whence it is drawn off occa- 

 sionally to be farther purified and separated. And sixth, to separate iron, 

 the oxides are discharged down a shoot, fixed at an angle of about thirty 

 degrees, formed of wood, or of some other non-conducting material, from the 

 bottom of which the poles of a number of magnets project upwards, and to 

 which a slow, lateral, sieve-like motion is given by machinery ; the magnets 

 attract and retain the iron, and the oxides pass free. — Jl/itl. 



IMPROVEMENTS IN IRON. 



J.\mks Pai.mkr IU'iid, of the Ystalyfera Iron Works, Swansea, fol 

 priirriiini/s in tlte manufacture oj iron." — Patent dated October 20, 1842; 

 Mr. liudd's improved process of manufacturing iron, as contradistinguished 



from Ncilson's ami (rate's processes, may be called the cold anthracite 

 blast. The points of novelty to which he lays claim are these — First, t lie 

 application of anthracite or stone coal, combined with a blast of atmospheric 

 air, in the natural or untreated state, maintained at a pressure or pxilar of 

 upwards of 2J lbs. on the square inch, in the smelting or manufacturing of 

 iron from ironstone, mine, or ore. Secondly, the application of anthracite 

 or stone coal, combined with the use of water tuyeres, and with a blast of 

 atmospheric air in the natural or indicated state, in the smelting or manu- 

 facturing of iron from ironstone, mine, or ore. Thirdly . the application of an- 

 thracite or stone coal, in combination with four or more tuyeres, and a 

 blast of atmospheric air in the natural or uuheated state. — Ibid, 



GAS. 



James Crutchett, of William Street, Regent's Tark, engineer, has ob- 

 tained a patent for " certain improvement! in manufacturing i/ax, and an ap- 

 /•nriitns 'fer consuming gas?' — Patent dated July l'J, lsij. — The " improve- 

 ments in manufacturing gas" consist in producing, by a peculiar apparatus, 

 described by the patentee, a triple compound, composed, first, of coal or 

 other gas j secondly, atmospheric air, (in the proportion of from ."> to la per 

 cent) ; and, thirdly, vapour of naphtha, or other volatile hydro-carbon, (in 

 what proportions is not stated). The most remarkable feature in the ap- 

 paratus employed for this purpose is, that the moving power which actuates 

 it is the gas itself. The improvements in " apparatus for consuming gas" 

 consist in substituting for the ordinary concentric rings a spiral coil, " by 

 which the light is. equally concentrated, with the advantage that only one 

 inlet-pipe is required." — Mechanic's Mag. 



dated July 6, 1812. — The plates are so rolled or constructed as to be per- 

 fectly smooth on that side which is to become the outer side of the vessel, 

 but along the two inside edges of the plate there are raised two bands or 

 strips, varying in breadth, according to the thickness of the plate, and, of 

 course, the strength of rivet to be used in joining them. The plates are to 

 be punched in the usual way, and afterwards counter-sunk on the outside. 

 In joining, the plates are brought edge to edge, being flush on the outside ; 

 and upon the inside is laid a piece of flat bar iron, pierced with two lines of 

 rivet holes, so as to correspond with the holes in the plate, to which it is to 

 be riveted. Where it is required to have greater strength, so as to resist in- 

 creased external pressure, the flat bar has a raised feather along its outer side, 

 the section of which will form that of a T. The bands, or strips, along the 

 edges of the plate are to be of such thickness as to make the plate of uni- 

 form strength throughout when pierced for the rivets ; and thus to obviate 

 the risk of the plates being broken in that part, which is generally, if not 

 always, found to be the result in cases of concussion, ixc. The rivets are so 

 made as to fill the countersink, and thus present a uniform smooth surface 

 on the outside of the vessel when completed, which of course must meet 

 much less resistance in passing through the water. — The claim is to the 

 manufacturing of plates, and joining them as above-mentioned, in the con- 

 struction of boats and other vessels. — Mechanic's May. 



A FIRE-PROOF POWDER MAGAZINE. 



An experiment was lately made at Paine's wharf, Westminster, for the 

 purpose of testing the capabilities of a magazine to contain powder in 

 ships of war, recently patented by Mr. J. A. Holdsworth, as being impervious 

 to fire, though subjected on all sides to the greatest possible degree of heat. 

 A model of a magazine, about nine feet square, was placed on the wharf 

 within a few feet of the water's edge. This model is formed of a double set 

 of thin iron plates, riveted together at about two inches and a half asunder, 

 the hollow being filled with water, and supplied from a vat placed somewhat 

 above the level of the magazine, and entering it through a pipe inserted 

 in the lower part of the model. A channel of communication exists through 

 ever] side as well as the top and bottom, and from the upper surface a second 

 pipe conveys the stream of water back to the vat from x\hich it is supplied. 

 The door of the magazine is hung on hinges, made hollow, anil guarded from 

 leaking by stuffing boxes, so that the water flows into the door through one 

 lunge and out through the other. The patentee having explained the prin- 

 ciple of his invention, placed a quantity of combustible matter within the 

 model, over which some gunpowder was laid on a sheet of paper. A regis- 

 tering thermometer having been placed inside, the door was closed, and a 

 stack of dried timber deposited on every side of the model, was set a-light. 

 The lire was kept up more than ball' an-hour, and the water rose to very nearly 

 boiling beat, continually passing in a stream through the upper pipe into 

 the reservoir containing cold water. On the door being opened, the eom- 

 buatiMe nutters and powder were found to be perfectly uninjured, and the 

 point to which the mercury bail risen within the model was marked 

 at LOO degrees of Fahrenheit. A somewhat similar principle has been applied 

 I" tin stoker's room in the Victoria and .llhert royal steam yacht, where the 

 bulkheads have been constructed of two plates of sheet iron, instead of 

 wood faced with iron, a stream of water constantly flowing between, by 

 which means the temperature of the engine room is kept cool. 



METAL SHIPS. 



William FairHairn, of Manchester, engineer, has obtained a patent for 

 " certain iin/iroecmenls in the construction of metal ship*, boats, and other 

 vessels, an ihe oration of metal vlates to be used therein," — Patent 



ORNAMENTAL GLASS. 



Mh. John Carr, of North Shields, earthenware manufacturer, and Aarov 

 ISvlks, of the same place, agent, have obtained a patent for " an iinproved 

 modt of operating in certain pmcettetfw ornamenting gluts." — Patent dated 

 9th November, 1841 ; which consists of improvements in toe operations of 

 staining, stopping out, and obscuring glass. In the improved method of 

 Staining glass, the staining materials, instead of being mixed with oil of tur- 

 pentine, or other volatile oils, or water, as usual, are mixed with boiled 

 linseed oil, or such other oil as is generally employed when printing with 

 enamel colours on glass; and instead of floating the staining materials over 

 the glass, hi a liquid state, they are printed or transferred from metal plates, 

 and, whin dry, are fixed by firing, in the usual way. When operating with 

 staining materials mixed with oil, as aforesaid, on pot metal, or on flashed 

 glass, opaque and transparent shades arc produced, leaving the surface of the 

 glass quite smooth, instead of being raised in those parts, as in the common 

 mode of applyitig body colour, for the purpose of shading. As regards the 

 operation of stopping out, the materials, used for that purpose, are mixed 

 with boiled oil, and printed on the glass, in the manner above described : 

 the liquid staining composition is then floated over the whole surface, in- 

 cluding the parts so stopped out, and the colour is fixed by firing. After the 

 glass has been cleaned, the pattern, which was printed on it in stopping out 

 materials, is exhibited in the original colour of the glass, and quite distinct 

 from the stained ground; or a printed impression being transferred to the 

 glass, in stopping out materials, as aforesaid, the remainder of the ground 

 may be obscured in the usual manner ; thus producing transparent patterns 



