1818.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



213 



under the lower end of the stem of the skimmer which is lowered 

 to take up the ore, it then passes through the stem into any 

 receptacle ])laced to receive it. By another arrangement of the 

 machine the skimmer revolves instead of heing fixed, and traverses 

 the ore at a regulated depth from the surface, and the waste is 

 carried by tlie rotating force and the stream of water into the 

 skimmer, and from thence into the central compartment, from 

 Whence it passes down the hollow shaft into the receptacle appointed 

 to receive it. The second part of the invention relates to a method 

 of dressing small ore and sleines of ore. A hollow frame or trunk, 

 has for its section the exterior form of a cone, which converges 

 to its centre from the extremes of its base, and terminates in an 

 aperture having a cock. To this centre is fixed an iron arm or 

 step, upon which the whole apparatus revolves. The apex is formed 

 like a goblet, for the purpose of a funnel, into which the small ores 

 are poured. On each side or limb of this trunk or ludlow frame 

 are attached three receptacles, the first opening from tlie trunk 

 into the uppermost one, being about one-tliird from the apex or 

 funnel ; the second communicating with the middle one, at about 

 two-thirds from the apex ; and the third at the angle or extremities 

 of the base. A pulley is fixed to the under side of the funnel, by 

 which a rotating motion is imparted to the whole of the hollow 

 frame, and the small ores in a moistened state are poured into the 

 funnel, and pass down the hollow trunk. The centrifugal force of the 

 revolving trunk causes the heaviest of the ores to ha discharged at 

 tlie upper opening into the adjoining receptacle ; the next less in 

 size into the middle one, and the least, or sleines, into the lower 

 one. The water which passes into the trunk with the small ore or 

 sleines of ore, is discharged by means of the cock at the base, 

 immediately above the step upon which the whole revolves. When 

 the receptacles are full, the small doors in front of each are removed, 

 and the ores are taken out and placed in the usual bins, according 

 to their various sizes. The patentee claims — first, the conveying 

 the ores and waste into another receptacle over the annular margin 

 of the sieve, by means of a skimmer-pipe and stream of water ; 

 secondly, the application of the force-pump ; and thirdly, the 

 application of centrifugal force for producing artificial gravitation- 



MANUFACTURE OF PIGMENTS. 



William Edward Newton, of Chancery- lane, for ^'•Improvements 

 in the mode or modes of manufacturing or preparing certain matters to 

 be employed as pigments." (A communication.) — Granted Novem- 

 ber 16, 184.7 ; Enrolled May 16, 1848. 



This invention relates to the manufacture of zinc-white, zinc- 

 yellow, and zinc-green, though it is principally directed to the forma- 

 tion of zinc-white, the other pigments having been the subjects of a 

 former patent. The processes are described at gi-eat length in the 

 specification, but the claims of the patentee will sufficiently explain 

 the nature of the proposed improvements. He claims — First, the 

 distillation of metallic zinc, of oxide of zinc, or zinc ore, by one of 

 several means mentioned. Second, the application of furnaces 

 similar to glass furnaces and coke ovens, and the modification of 

 them respectively in order to fit them for the purpose of manufac- 

 turing zinc-white. Third, the construction of furnace, formed of 

 two cylindrical tubes placed side by side with furnaces or fire- 

 places formed in the lower part of the brick-work. Fourth, the 

 isolating the retorts from each other and also cutting off the com- 

 munication between the retorts and the oxidizing chamber when 

 required. Fifth, the employment of suitable apparatus for cleansing 

 the mouths of the retorts without being obliged to enter the oxidiz- 

 ing chamber. Sixth, the arrangement of apparatus by which the 

 retorts may be charged, cleansed, and replaced, or submitted to 

 any operation required, without interfering with the oxidizing 

 chamber. Seventh, the application or employment of blast furnaces 

 for the production or manufacture of zinc-white or oxide of zinc, 

 whether such furnaces are circular or of any other suitable form, 

 and whether they are constructed and arranged in a vertical, 

 inclined, or horizontal position. Eighth, the employment or intro- 

 duction of currents of air into an o.xidizing or other chamber, for 

 the purpose of converting the metallic vapours of zinc into zinc- 

 white or oxide of zinc ; also the employment of an exhaustion-tube 

 or blowing-apparatus for conducting the metallic vapours to the 

 oxidizing chamber. The patentee claims also the employment of 

 wire-gauze or sieves for sifting the products ; also the arrangement 

 of vessels for receiving the heaviest portions of products. Ninth, 

 the arrangement of the oxidizing chambers so as to aUow of the 

 products being collected without the necessity of entering them. 

 Having described all that appertains to the manufacture and man- 

 ner of collecting zinc-white, the patentee next proceeds to an 

 explanation of that part of the invention which relates to the 



yellow of zinc and green zinc. As the manufacture of zinc-yellow 

 forms the subject of a previous patent, he merely remarks that 

 hydrochloric acid may be used instead of sulphuric acid. To form 

 zinc-green, yellow (having been produced by the patented process,) 

 is diluted with a suitable quantity of water, and mixed witli a cer- 

 tain quantity of prussian blue (previously mixed with a suitable 

 quantity of water, oil, or otlier appropriate liquid), either in a hot 

 or a cold state. Green of zinc will thus be formed, the colour of 

 which will be as durable as the blue itself. These pigments may 

 be employed for painting of any kind. 



SMELTING COPPER ORES. 



William Bibkiuyre, of Southdown, Cornwall, for " Improve- 

 ments in smelting copper and other ores." — Granted November 16, 

 1847 ; Enrolled May 16, 1848. 



The chief object of this invention is to remove the nuisance 

 arising from the sulphuric and sulphurous acid vapours, and from 

 the vapours of arsenic, during the smelting of copper ores. The 

 process is thus described : — A double iron pyrites kiln is constructed 

 upon the usual principles, the ash-pits being furnished with a 

 leaden cistern, filled with water, to abate the nuisance arising from 

 the sulphurous and arsenious acids, when drawing out the mundic 

 ashes. Over the charging-door for the mundic, is an air-hole, 

 provided with a damper, to regulate the passage of the oxygen 

 necessary for combustion. The size of the double iron pyrites 

 kUn should be 13 feet long, 7 feet 4 inches wide, and "8 feet high, 

 and each furnace should be 5 feet in diameter, and of an octagonal 

 form, lined with fire-bricks. Above the charging-door for the 

 mundic, resting on two or three bars, is a tray, made of iron or 

 copper, 4, feet 6 inches long, 3 feet 6 inches \ride, and having a 

 rim round it three or four inches deep. This is so placed as to 

 enable the air and acids to pass freely out of the top of the furnac* 

 into a vitriol chamber, which is placed over the kUns. The vitriol 

 chamber should be 150 feet 6 inches long, 11 feet 3 inches wide, 

 and e feet deep, divided into three compartments, technically called 

 " bottoms." The acid in that compartment nearest to the kiln 

 being impure, should be kept apart, but the acid in the second 

 and third compartments will be found to contain good vitriol. 

 These pair of kilns will be found capable of producing two tons of 

 copper per diem, by means of mundic, and, at the same time, of 

 three tons of vitriol of a specific gravity of 1-847. The copper ore 

 being broken into pieces, about the size of walnuts, is put into the 

 tray by means of a shovel or hopper (the furnace being charged 

 with iron pyrites and previously kindled). After a lapse of six 

 hours the other kiln is to be charged in like manner, and so on 

 alternately. For every 8 cwt. of mundic ashes withdrawn, add a 

 charge of 10 cwt. of mundic containing 40 per cent, of sulphur, as 

 for every 32 parts of sulphur it loses, it gains only 12 parts of 

 oxygen ; but in copper ores, if the process is carefully completed, 

 it gains as much in oxygen as it loses in sulpliur ; some copper ores 

 it is stated will gain as much as four per cent. About li cwt. of 

 ore should be placed in the tray, and the charge should be sj>read 

 out into a body of from one to two inches thick, which should be 

 turned over now and then, in order that every part of it should be 

 exposed. Alter being submitted to the process for one hour, it is 

 to be turned into a leaden cistern, supplied with hot water from 

 the cooling cisterns underneath the kilns, to undergo the process 

 of lixiviation. The tray is then again charged with ore, and the 

 process is continued. It requires two roastings and lixiviation by 

 the electro-metallurgic process to obtain the pure copper. Another 

 method of calcination is, when the pulverized copper pyrites are 

 exposed in the tray, pour upon them a hot solution of nine parts 

 of saltpetre, and eight parts of cubic nitre, or 16 per cent, of salt- 

 petre and 10 per cent, of vitriol, or equal quantities of saltpetre 

 and vitriol to half the quantity of the ore. By this system, the 

 deutoxide of nitrogen, necessary for making vitriol on a lai-ge 

 scale, is separated, and the oxidation of the ores accomplished. 

 The patentee claims— First, the roasting separately common ores 

 of copper and other metals, by exposing them in an open vessel in 

 a muudic-kiln, so that the vapours shall freely mix with the vapours 

 of combustion of the iron pyrites, and be condensed at the same 

 time in the vitriol chamber. Secondly, the separating simulta- 

 neously the deutoxide of nitrogen, for the vitriol chamber, with the 

 oxidation of the ores, by saltpetre or cubic nitre. Thirdly, the 

 supplying the vitriol chamber with steam, by using saltpetre or 

 cubic nitre ; and, fourthly, the action of sulphuric acid upon the 

 ores, either before or after they have been freed from the sulphate 

 and arsenic of potash and soda. 



