151
the meta], a quantity of warm air, from the pipe ft, is conducted through the pipe k,which is divided into two nozzles or tuyeres 11 , and blown upon the fluid metal in thes Pace d d. After having been thus exposed for an hour or two, it is run off throughthe opening m, and will be found in a refined state.
Figs. 77, 78, show the application to a puddling furnace. The openings n n admita stream of cold u r ater to flow through the cast-iron piece o o, to preserve it from injuryhy the lire.
77 78
Wr'M
■ami
Fig. 79 is a welding furnace; the interior dimensions and the casing of the hearthbeing different, as well as the lire bridge, from those of the puddling furnace. ThePtpes for conducting the gases are made of cast-iron, and must have at least a sectionalar ea of one foot for every furnace that is to be heated.
Figs. 80, 81, 82, 83, 84, show the application of this invention to the generation of8 *eam. A chimney is here employed only at the commencement of the operation. The
79
b'r is forced into the furnace by any sort of blowing machine, or in any other con-'cnient way. The fuel is introduced into the fireplace, upon the grate n n, throughA e door a, which can be closed. The fireplace must contain as much fuel as will last°r several hours. When the fire is first lighted, the combustion takes place in theQuinary way, on opening the door d, and the slide-valve ft, and carrying through themj, current of air by the chimney draught. This is continued till the steam-engine. llr nace, or any working (power) engine is in operation, after which a blowing apparatusemployed to force the air through the tube c , as shown in fig. 81. The openings d'ltd hare then closed; the air forced in now passes through"the flues/,/,/, placed° a nd and beneath the boiler. The air, on arriving at the point g, is divided, onePortion passes through the opening h, regulated by a valve, into the open space beneathlle grate n n, to assist in the slow combustion of the fuel. The other part of the air1 a sses through g, into h h, round the fireplace, in order to heat the air to an intenseo e gree. After the second portion of the air has passed into the chamber h h, it entersbother i i, thence through a series of blowpipes, or through o, into p p, beneath the