Specification of John Ferguson : furnaces and fire-places.

  • Ferguson, John.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: Specification of John Ferguson : furnaces and fire-places. Source: Wellcome Collection.

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    Provisional Fergusons Improvements in Furnaces and Fire-places, §c. horizontally into the seating, and passes in each case by a slight bend into a narrow horizontal flue formed in the seating, just beneath the level of the flame bed, beneath the boiler and behind the bridge. This flue runs along beneath the flame bed, and is only separated therefrom by a slight thin cover to the further end of the boiler; here 5 it takes a bend outwards, and returns back to the front end in a line parallel to the first run of the flue, and at the same level. In this way the cold air takes up considerable heat from the flame bed, and in this heated state it is passed amongst the gases as they pass from the grate. For this purpose the extreme front end of the flue passes by a short 10 bend or angle towards the line of the boiler’s centre, and here enters the outer end of a hollow or cellular bridge standing up from the base of the seating at the back end of the grate bars. Precisely the same arrangement is followed out on each side of the boiler, and the hollow bridge has a central division across it to prevent the mingling of 15 the two currents. At the back of the hollow bridge are a set of openings or jet passages, so that the heated air supplied to the bridge chamber can thus escape in a diffused state on the side furthest from the grate bars ; here the air jets mingle with the gases, passing over the front hollow fixed bridge, and the whole current of mixed heated air 20 and gases then passes onwards and strikes against the front of a vertical hanging bridge of considerable depth. This bridge stops the progress of the current, and enables the component matters thereof to become fully mixed. In this state the combined current descends and passes beneath the bottom edge of the hanging bridge, and rises up at the 25 other side and over the top of a third bridge or flame spreader into the flame bed. Thus there are, as it were, two mixing chambers for the air and gases, and the whole become well commingled, whilst an economical use is made of the flame bed heat in passing the cold air along the bottom flues. Although this arrangement has been specially 30 mentioned in its application to a certain kind of steam boiler, yet it is equally applicable to all other varieties of furnace or fire place, whether for steam purposes or not.