facilitate contact of the flame with the article to be heated. Lighting up is done with flaming waste or shavings, and the air is regulated to the oil, the opening of the passage from the generator to the furnace being higher than the atomizer. The fire becomes white when the generator has become hot, and regulation then ceases. Good results are got with two inches of air pressure in the pipes, and about 11 inches in the generator. About 40 pounds of oil per hour will be consumed. Six smiths will use an ordinary furnace. Two of them will work objects of some size, and not be in the way of the others. Larger objects require double furnaces with a central chimney, two fire beds, and two generators. Brick or Lime Kilns. In one form of kiln the brickwork of the kiln contains three to five basins, kept full of oil by means of pipes. Air for combustion is brought in by slots between the basins. Copper also, and other metals, may be melted in crucibles. In one works, at Chemnitz, a malleable cast iron is made in crucibles heated by oil, the vapour of which is mixed with hot air before entering the combustion chamber in which the crucibles stand two and two. In other apparatus oil falls drop by drop or in fine streams; the vapour, brought into contact with air, burns freely and gives a high temperature. This class of apparatus is successfully employed for re-heating and brazing or welding, but the oil must be gasefied in a particular space before the flame is applied to its work. Atomizers may also be used for metallurgical furnace work, actuated preferably by air. In the recuperative Siemens-Martin furnace the depth of the air chambers and of the gas chambers placed directly under the bottom should not be too great, because the vapour of oil contains less carbonic oxide than does coal gas, and is liable to condense if left too long in the state of gas, and form tars and coke. Across the front wall of the recuperator is fixed a thick iron plate with an opening through which passes a hollow fitting of iron with the oil tube. Oil is supplied by the tube, and spreads over the fitting of iron previously heated. It gasefies and at once passes to the furnace by two passages, air coming in by three other openings. The iron vaporizer is heated by an atomizer. In a puddling furnace on this principle were produced in twenty-four hours five to six tons of iron. The loss was seven to eight per cent.. and the consumption of oil 550 pounds per ton of finished metal, which represented an economy of 80 per cent. as compared with The Kirting atomizer (fig. 19 is much used in Siemens-Martin furnaces, oil being pamped at 75 to 105 lbs. pressure into an accumulator, whence it passes by a pipe to the atomizer, which plays directly into a heating chamber whence issue the heated vapours to the furnace, where they mix with air introduced by Slits below the opening for the vapour. With a furnace of 10 to 15 tons capacity. the consumption of oil is 20 per cent. of the weight of metal. Other simple furnaces have the oil introduced by five air-worked atomizers, two at each end and one in the mid le of the furnace. The atomizers are water jacketed for protection. Oil greatly sin.plifies the work of attendance, the highest heats are obtained, and the fire can be extinguished any time and fuel saved. Furnaces are as durable as gas heated furnaces and have as high an output. Copper Smelting. In the Caucasus at Kedabeg and Kalakent the melting of ores roasted in the heap for the production of copper matte is done in reverberatory furnaces heated by oil, as also is the refining of crude copper. The furnace for ore smelting consists of a working chamber with a quartzose floor, and covered with a very flat vault or arch. Two steam atomizers and two air tuyeres are placed symmetrically at the back of the furnace, the air and petroleum obliquely towards the front. The two oil jets, in flames, having crossed the circular furnace nearly diametrically, recurve in semicircles and escape by a flue opening close to the injection openings. The flames act by reverberation. A furnace will pass 40 tons of ore of 7 per cent. quality in 24 hours, with one skilled man and three labourers. Chapter XXXI EXAMPLES OF LIQUID FUEL CARRIERS BY RAIL AND SEA IT Oil Carriage by Rail. is of great importance that the carriage of oil by rail should be conducted only in such vehicles as are safe in case of the most severe accidents occurring to the train of which they form a part. The form now considered best is that of figs. 115 and 116, for which I am indebted to Messrs. Renshaw & Co., Limited, of Stoke-on-Trent. They show an all steel railway tank wagon having a capacity of 2,800 gallons of oil at a specific gravity of 82, being one of ninety built for the Shell Transport Company. The shell plates are made in one length, inch thick and the dished ends are inch thick. The manhole is provided with a screwed cover, thereby forming an air-tight joint. The outlet has a plug valve worked by a handwheel at the top of the tank inside the manhole, and to the stool in which this valve rests is connected a wrought iron branch tee piece giving two outlets, one on either side of the wagon. These have each a 2 inch gun metal sluice valve, and the end of the pipe is covered by a gun metal cap to protect the screw to which hose coupling may be attached for discharging the oil. A wagon throughout must be of high-class workmanship, the whole of the riveting being done by hydraulic and pneumatic machinery, and the tanks must be tested to 20 pounds per square inch pressure, and must be absolutely water-tight before being passed. The steel underframe should be of exceptional strength, a special feature in the wagon illustrated being the method by which the sole bars are joined to the head stocks, both by flanging of the bars and by cover plates. The axle-boxes have open sliding fronts to allow easy access to the grease chambers, and altogether an oil wagon must be strongly and soundly built. The oil tank is attached by four side brackets to the framing, and is also supported at each end against the headstock by blocks of timber. There is a longitudinal stay plate between the two dished ends and a pair of diaphragm or swash plates to distribute surging stresses throughout the whole tank structure. Made of tough steel plate of boiler quality, such a tank should bear a good deal of rough usage or collision without failure. are riveted, and the rivets are spaced, for oil tightness, 3 diameters centre to centre, instead of 4 diameters as required for water-tight work. Special care is 286 than two Fig. 115. TEN TON RAILWAY TANK WAGON FOR OIL FUEL. In Fig. 117 is illustrated the oil carrying steamer, Newyork, built by the Palmer's Shipbuilding and Iron Company, Ltd., of Jarrow-on-Tyne. In this class of vessel all the seams and butts of the shell plating, decks, and bulkheads RENSHAW'S LIMITED, ETRURIA |