Disposition of the fires and furnace.—[Fig. 586.] represents, upon a scale three times larger than [fig. 585.], the section of the fire X, of which the plan is seen in [fig. 585.], and the elevation in [fig. 583.]; as also in the outside view of the blast furnace, [fig. 589.]
The grate is at L; the fuel is introduced by the door P, [fig. 583.]; the flame rises above the bridge I K, and proceeds along the vaulted flue towards the chimney H. Through a length of about 13 feet including the grate, the furnace is on each side supported by oblong plates of cast iron, which are bound together by 4 upright ribbed or feathered bars, also on each side; these bars n being bound together by iron rods furnished with screw nuts at their ends ([figs. 583], [585], [586.]) Beyond this distance, the outside of the furnace is mere brickwork.
The fires Y and Z have exactly a like disposition with the above.
[Fig. 586.] indicates the dimensions and the curvature of the arch above the grate, near the bridge; [fig. 587.] represents the section of the furnace and of the pipe beyond the cast-iron casing.
I find that the furnace is only about 3 feet wide at the bottom, and that the elevation of the arch above the bottom is no more than 30 inches. Perhaps it might be made a little wider with advantage; the combustion would be more vigorous and effective; and if the sides also were a little thicker, the heat would be better confined.
| The distance from the fire-place | X to the chimney H, is | 43 | 1⁄2 | feet. | ||
| The di—ance from the fire— | Y to the point C, is | 13 | — | |||
| The di—ance from the fire— | Z to the chimney, is | 29 | — | including the turn of the elbow E. | ||