" The fire is placed at the end, under a horizontal bed of fire-brick some twelve or fifteen feet in length—the fire passing through to the other extremity. In the cen tre, and over the bed, is erected a double cylinder, which is filled with crushed ore and pulverized anthracite coal. The in tense flame surrounds the cylinder, and also passes through the inner cylinder, which removes the oxygen and all other impurities with the presence of atmos pheric air. Being thus prepared, the ore gradually melts and descends to the hearth, where it first comes in contact with the fire, which destroys the remain der of the pulverized coal by frequent stirring, and the iron is thus partially formed. From this hearth it is thrown to another about eight inches lower than the first, where it is worked into balls of about one hundred pounds amid the same sheet of fire, and in a few minutes the ball is withdrawn and put under the hammer to put it in shape, which con cludes the _process.
Mr. Wall, of England, has patented a process fo'r removing the phosphorus out of iron. The process consists of two parts ; first, in adding certain substances to the metal, while in a state of fusion ; 2nd, in applying electricity to the metal while in a state of fusion, and during its cooling. In carrying out the first part, two compounds are made use of, termed A and B.
The compound A is formed by mix ing two parts of iron filings or turnings with five parts of black resin, by melting the resin and stirring in the iron filings. When the mass has sufficiently cooled it is made into balls of about five pounds weight each ; and in using them these balls are thrown in the melting-furnace on the surface of the fused metal, in the proportion of one of the balls to every 5 cwt. of metal. The compound B is formed by thoroughly mixing two parts of common salt and five parts of resin, turpentine, or other carbonaceous matter, and nicking this also into balls of about five pounds each, and throwing these on to the surface of the melted metal, in the proportion of one pound to each cwt. of the metal, after the compound A has been employed. In carrying out the sec ond part, a battery is employed, consist ing of platinum and zinc plates, contain ing eight pairs, 6 inches by 4 of active surface, in separate cells of dilute sul phuric and strong nitric acid, arranged in the manner commonly known as Grove's battery, or 32 pairs of seine sized plates, arranged in the manner commonly known as Sinee's battery, which give suf fieent electricity for all general purposes. In applying the electric current a rod of iron is inserted into each extremity of the mould, into which the metal is to bo cast, if the casting be horizontal ; or into the bottom and top of the mould, if the casting is vertical. These two rods of iron are connected with the two poles of the battery respectively ; and when the melted metal is poured into the mould, it serves to complete the circuit, and elec tricity will continue to traverse it as long as the connection with the poles of the battery remains unbroken. The current should be kept up for a considerable time even after the metal has ; but if continued for too long a time, the metal would be decarbonated and convert.. ed into wrought iron. The patentee also passes an electric current through the fused metal while in the furnace, by inserting a rod of iron in the lower part of the furnace so as to be in contact with the metal, which rod is attached to one pole of the battery, while another rod in connection with the opposite pole is moved by the operator in constant con tact with the melted mass, over every part of the surface, thus directing the current through every portion of it.
Overman, in his work, says, " Hydra ted Oxide of Iron, Brown Oxide, He matite Bog Ore, should all be roasted, not for the purpose of oxidation, but to drive off the acids, and destroy the sul phurets and phosphrirets—all ores of this class contain more or less injurious mat ter. Sulphates of iron should be care fully roasted, so should phosphates, with a liberal access of air." The more carbon that is present, the greater difficulty there is to drive off the phosphorus, for carbon is necessary in every case to produce a combination of phosphorus with the metal—the process of Wall, therefore, in expelling the car bon, would lead to infer that it would be most suitable for the removal of phos phorus, and sulphur also.
Mr. Thompson, of Newcastle-on-Tyne, England, has patented an improved fur nace. The nature of the invention con sists of two parts. First, the construc tion and working of the furnace. Sec ond, the application of the gases genera ted in the furnace to subsequent useful purposes.
The body of the furnace, is constructed somewhat in the ordinary manner ; the top of it is of a dome shape, and sur mounted by a throat, the upper end of which can be closed by iron plate, which is intended to fit as air-tight as practicable, and when removed, it is through this aperture that the furnace is charged. Above the dome, and around the throat, is the circular tunnel or chamber ; it com municates by the apertures or short flues, with the body of the furnace in the upper part of the dome ; from this tunnel, upon opposite sides of the furnace, proceed vertical pipes ; these are intended to carry off the gases ; two steam pipes at their lower ends communicate with a steam boiler behind the furnace, from which the steam is supplied : the steam pipes pass upwards into the centre of the ver tical pipes, and their ends terminate in a number of steam jets, arranged so as to produce the best effects of exhaustion ; the tuyers are arranged in the usual manner and intended to supply air to the furnace by draught, either in a cold or hot state. The exhaust pipes are about eighteen inches in diameter, and the diameter of the steam pipes is about four inches. The steam jets being in action, they cause an exhausting action in the pipes, thereby drawing the gases generated in the furnace through the short flues and tunnel, and eft. fecting the necessary working ot the fur nace. The lid is lifted from its seat oc casionally, for the purpose of charging the furnace, but this is to be done as sel dom as possible, as at these times the ex hausting action of the steam jets is to be stopped, and the consequent working of the furnace suspended. This method, therefore, is to do away with the blower, and use exhaust by steam as a substitute. The second improvement is, the em ploying the gases generated in the fur-. nace, in the above described operation, to subsequent useful purposes, as heating the refinery and other furnaces, or genera ting steam in steam boilers ; to effect this, the vertical pipes are dispensed with, and the gases generated are carried by a pipe from the tunnel to the furnace where they are to be employed. The steam jets or other exhausting means are then em ployed in the exit or chimney from this furnace, instead of the smelting furnace, as above.