Gas-house Coke
This class of coke is invariably unfit for cupola purposes, because it has not sufficient cohesiveness to sustain the weight of the charges above, and therefore crumbles, allowing much of the combustion to take place before it reaches the melting-point of the cupola, at which point it is always desirable to have the fuel compact and in good form to meet the full force of the blast. See COKE; COMBUSTION.
Gas-pipe Vents are a safe and simple means of leading away the gases from vents where there is any possibility of molten metal forcing its way therein. If iron block-prints are used on the cores, as in steamway cores of cylinders, the ends may be threaded to screw into vent-holes that have been previously tapped in the iron print; if the print is sand, then taper the pipe about one inch, so that it may enter snugly. Venting that ordinarily would be intricate and untrustworthy is by this means made absolutely sure. See VENTING.