HORIZONTAL ROTARY RETORT.

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mouth of the retort, when the coals are to be intro-duced, or coke is to be withdrawn. To the upperextremity of the rod B, fig. 1, plate II., is fixed alever, loaded with a counterpoise weight C, tobalance the door, and to render the opening andclosing of it easy and expeditious.

The mouth-piece and its door is three feetlong', and nine inches wide; it projects nineinches beyond the brick-w ork or furnace in whichthe retort is fixed, as may be seen at fig. 1, plateII.

The fire-place, which is on the opposite side tothat of the mouth of the retort, heats only one-thirdpart of the whole capacity of the retort to that de-gree which is proper for the complete and rapiddecomposition of the coal, while the remainingparts, which are not over the fire-place, and towhich the fire flues do not extend, are kept at alower temperature.

The flues are directed under about one-third ofthe area of the bottom of the retort, and after havingpassed over one-third part of the area of the top ofthe retort, they pass into the chimney. Fig. 1, plateVI., exhibits the direction of the flues ; A, A, the

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