Lewis’s White Lead Plant.
the escape of the crushed ore and coal. These perforated bars are suitably sustained at the ends on the front and back walls of the furnace. The ash pit below the perforated bottom is of equal area therewith, and is provided with a door e in front, and with a hole f at the back for the reception of a pipe from suitable blowing apparatus.
The walls g, and arch on the top should be built of some refractory substance, such as fire-brick.
The front of the furnace is entirely open, and is provided with sliding doors i, by which it can be closed when working, and opened to remove the residuum.
At the back of the furnace there are two slides j, to permit access to the main chamber, for stirring the charge and for inspection.
At the back, near the arch, there is a hole k, governed by a sliding damper leading to a chimney, for carrying off smoke and impure gases at the commencement of the operation upon a new charge.
In the centre of the roof there is an aperture l, governed by a damper or sliding door m, the said aperture leading to a suitable apparatus for the collection of the oxidised vapours of lead.