320 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[Oct. 



length ; but this may greatly exceed the length of ordinnry retorts, on 

 account of the facility of working at bo:h ends, which the patentee 

 considers an important feature of his invention. The retorts have 

 caps /, fitted on each end, furnished with exit-pipes^', for the gas. 

 Any accumulation of coal-tar is removed from the retort, by partially 

 opening one end of the retort, and applying an extra pipe to the 

 op[)osite end; which pipe then acts as a flue, and the draft of air 

 through the heated retort completely removes the carbonaceous de- 

 posit. 



The patentee states, that the description of the manner of applying 

 liis improvements to a furnace for generating gas will enable a person 

 to apply such improvements to furnaces for otlier purposes. He claims 

 the general arrangement of the furnace and flues as described, which 

 ronsists in a continuous lire-place from one end to the other, supplied 

 with air from parallel air-Hues — thus allowing the heat to bi" cunducted 

 from end to end, or from end to centre repeatedly; together with the 

 peculiar form and construction of tile or fire-clay tubes, and the tiles 

 forming the joints, as above described. 



COOLING COKE OVENS. 



Frederick Ransome, of Ipswich, Suffolk, for "Improvements in 

 Korhing coke and other kilns or oreHS."— Granted Feb. 24; Enrolled 

 Aug. 24, 1847. 



This invention consists of improvements in cooling coke and other 

 kilns or ovens, by causing air to circulate by mechanical apparatus 

 through the cooling flues or passages. 



In the working of coke ovens the cooling has been extensively done 

 by having air passages arranged so as to allow air freely to circulate 

 in contact with the iiuier lining of the oven, the air not coming in 

 contact with the charge, such circulation being caused by the rarefac- 

 tion of the air by the heat of the flues. Such mode of working cuke 

 ovens is according to a patent granted to Jabez Church, December 2it, 

 1845. This mode of making coke is very superior to the old mode 

 where the charge is drawn when hut, and cooled down by water. In 

 working of such coke ovens, it has been found that the lime of cool- 

 ing an oven is very uncertain, depending on the state of the outer at- 

 mosphere, and that it is important to cool down the charge as quickly 

 as possible, so long as the atmosphere is excluded from the charge. 

 In coke ovens constructed according to Church's patent, the air after 

 })assing through the flues simply rises through a short pipe into the 

 ?.ir by its levitv, the pipe haviuj^ little, if anv effect, in causing the 

 circulation or passage of the air through the flues. But it has been 

 found that by hastening the draft in ovens arranged with flues, the 

 cooling process may be materially quickened. And this the patentee 

 prefe.-s to do by connecting the cooling flues with a rotatory fan, in 

 such manner as to continuously withdraw the air from such flues, by 

 which means the external air will rush into the flues or passages, and 

 thus cool the same quickly, and by these means the charge in the oven 

 will also be quickly cooled. 



The patentee does not confine himself to the fan, as other known 

 arrangements of blowing and exhausting apparatus may be employed, 

 or in place thereof the air or cooling flues or passages, or the pipe 

 thereof, may be conducted into a high shaft or chimney ; thus adding 

 additional power of exhaustion to that which results from the heat of 

 the passages or flues. 



CAOUTCHOUC. 



Stephen Movlton, E«q., of Norfolk-street, Strand, Middlesex, 

 gentleman, for " Iinprovjmnts in treating caoutchouc with other mate- 

 rials, to produce elastic and impermeable compounds." — Granted Feb. 

 S; Enrolled Aug. 8, 1847. 



This invention consists in treating caoutchouc by combining there- 

 with calcined and carbonate of magnesia and hyposulphate of lead 

 and the artificial sul|ihuret of lead, and submitting the combined com- 

 pound to heat, which process dispenses with the use of solvents. 

 After the caoutchouc has been cut and cleansed, one or more pounds 

 weight, as can be conveniently ground or mixed at a time, is put 

 between two revolving iron rollers, heated internally by steam, when 

 it presents a rough, miifurm sheet, and is then ready for the mixing it 

 with the following ingredients. 



If the goods are intended to be elastic, and to be unaffected by heat 

 or cold, mix in wilh 1 lb. of caoutchouc, from 1 to 8 oz. of the hypo- 

 sulphate of lead and the artificial sulpliuret of lead, both or either, 

 but the patentee prefers them in equal proportions; but if they are 

 used separately, then the whole quantity mentioned will be used. If 

 the goods are intended to be hard, of greater tenacity, and of less 

 elasticity, mix in from 2 to 8 oz. of tlie calcined or carbonate of mag- 



nesia with 1 lb. of caoutchouc, and then add both the hyposulphate of 

 lead and the artificial sulfihuret of lead, or either, in like manner and 

 proportions, as used for elastic goods. 



The materials above-mentioned and the caoutchouc having been 

 passed repeatedly between the mixing rollers, so that the whole com- 

 pound may be well combined, it is then removed to another pair of 

 rollers denominated the grinding rollers, and treated in like manner, 

 which rollers are placed nearer to each other than the mixing rollers, 

 in order that by these rollers a more perfect mixture of the compound 

 may be etfected. After this second process, the compound is again 

 removed to the third pair of rollers, also heated by steam, denomi- 

 nated the softening rollers, and again ground or mixed thereby, when 

 it soon becomes fit for its removal to the spreading machine. 



The spreading machine comprises two or more iron cylinders, which 

 are heated internally by steam (the machine preferred consists of three 

 rollers one above the other), and of a smoother and finer surface than 

 that of the rollers before-mentioned. The compound is placed be- 

 tween the upper rollers and passes to the lower one, upon which the 

 cloth for its reception passes round, and thus receives on its surface 

 the different coatings of the compound required. If sheet rubber is 

 desired, the compound is placed in like manner, dispensing with the 

 use of the cloth, and the sheet taken from the lower roller. Both the 

 coated cloth and the sheet rubber in passing off the lower roller are 

 rolled up in dry cloth to keep the surfaces apart, and is then fit for 

 making up into such goods as may be required. In manufacturing 

 goods from the compounds thus prepared, when manufactured, they 

 are dusted over with purified pipe or other cl.iy of similar qualitv 

 finely powdered, to prevent the surfaces from adhering together; but 

 they are as yet still liable to the action of all the solvents and other 

 influences which act upon caoutchouc, and would accordingly become 

 rigid in cold, and soft and sticky in warm weather ; to free the caou'.- 

 cliouc therefore from these, its natural characteristics, it has been com- 

 bined with the salts of lead above-mentioned, and the goods manufac- 

 tured from this compound have now to be subjected to heat in a suit- 

 able chamber or cylinder, and heated either by steam or dry heat (the 

 former is preferred) of from 22(J° to 280^ or 3Ua°, according to the 

 quantity of the goods heated at one time, and also as to the thickness 

 of the compound put into the sheets or upon the cloth. 



The time required for heating goods will likewise vary according 

 to the circumstances last mentioned. Some heats may require three 

 hours, and some five hours or thereabouts, and which is easily deter- 

 mined by any practical man acquainted with the business. After the 

 goods have been heated, as last mentioned, they become elastic aud 

 impermeable, as set forth in the title above recited. 



RAILWAY SWITCHES AND TURN-TABLES. 



Charles Heard Wild, of Mortimer-street, Cavendish-square, 

 civil engineer, for "Improvements in constructing parts of railways," 

 —Granted Feb. 24; Enrolled Aug. 24, 1847. [Reported in the 

 Patent Journal.'] 



The improvements here specified relate severally to the form of 

 the points of the moveable tongue rails of railway switches, and to the 

 construction aad application of certain mechanism to turn-tables, to 

 facilitate their action. The object of the patentee being to remove, 

 by the first of his improvements (namely, that improvement relating 

 to railway switches) the objections attendant upon switches of the 

 usual construction. These objections being, as stated by the patentee, 

 of two kinds, — one of which as an alternative it has hitherto been 

 necessary to adopt, as follows, — When the point of the moveable 

 tongue rail has been made sufficiently broad and strong to support 

 the weight of the wheel and the load of the carriage, it became 

 necessary to have a notch in the fixed rail to allow the inner edge of 

 the point of the tongue rail to coincide with the inner edge of the 

 fixed rail, so that there might be no impediment or interruption to 

 the flange of the wheel upon passing the point, while the switch is 

 closed; thus far, mhtle the switch is closed, no important objection ex- 

 ists, as usually constructed, as they present an unbroken siirlace of rail 

 to the passage of the carri.ige wheels; but the contrary is the case, 

 when the switch is opened: the notch now presents its objections and 

 disadvantages to action, the carriage wheels in passing striking 

 against the side of the notch. The alternative of this objection is, 

 making the depth of the notch much less; but to allow this, it is 

 necessary to redme the thickness of the point of the tongue rail, 

 thereby rendering it too thin and weak to support the passing weight. 

 These objections and disadvantages the patentee proposes to remove 

 by the improvements in question, and which consist in cutting away 

 so much from tlie upper table, and from the outer side of the middle 

 Webb of the moveable tongue rail, at the immediate point or extrem- 



