OPERATION OF THE MACHINE.
"When the charge of pig iron is melted and ready for the commencement of the pro cess of puddling, the apparatus is put in action by simply dropping the notch in the handle of the rabble, or the pin in the working arm, which is kept continuously in motion by the horizontal reciprocating T-bar working overhead. The puddler changes his tool from time to time, as it becomes heated, by simply lifting the notch in the handle off the pin in the working arm, and replacing the tool with a fresh one, without stopping the machine; and when the iron begins to thicken, he takes the opportunity of each change of tool to make a few strokes by hand, in order to collect the metal from the extreme sides of the furnace into the centre, which is found to insure the whole charge being uniformly worked. The usual time of working with the machine is about 25 minutes with ordinary forge pig iron, the tool being changed five or six times; but with gray iron the time of working is much prolonged.
"In the latter case the machine is especially serviceable, since the iron keeps in a fluid state much longer, and requires, consequently, so much more working; which causes the labor to be so much more severe in the case of hand-puddling that there is great difficulty in getting men to work any iron that is very gray. With the machine, however, this causes no increase of labor to the men, and only increases the time of the process.
"When the iron begins to thicken, or, as it is termed, 'coming to nature,' the machinery is disconnected without stopping it, by simply knocking out the cotter that fixes the upper end of the vertical working arm; the arm then drops. out, leaving the furnace-door entirely clear for the puddler to ball up the iron, which is done exactly in the same manner as in ordinary puddling-furnaces, without the man being in any way inconvenienced by the machinery continuing to work overhead.