KITCHENS OF COUNTRY INNS. 7^9 knowledge, that was so absurd as this ; it would not be difficult to prove, he says, " that much less than one thousandth part of the fuel that is necessary to be burned in an open chimney fireplace, in order to cause a smoke-jack to turn a loaded spit, would be sufficient to make the spit go round, were the force evolved from the combustion of the fuel, if it were properly directed, through the medium of a steam-engine." Besides this waste of fuel and of power, smoke-jacks require a lai'ge fire when it would not otherwise be wanted, by the necessity which they create for a great current of air up the chimney, to prevent it from smoking. This also increases the current of cold air from the doors and windows to the fireplace ; and thus, while the side of the cook next the fire is burned, the other is chilled. A jack moved by a weight or spring, if roasting must still be performed by the barbarous practice of turning meat on a spit before an open fire, is much prefoable ; and the trouble of winding it up, which is the general argument against it, is much less than that of burning coals to feed the immense tire that is requisite to cause a common smoke-jack to move. 1483. The Objects in view, in the Arrangement of a Kitchen, Count Rumford obsen'es, ought to be the following : — " 1st, Each boiler, kettle, and stewpan should have its separate closed fireplace. " 2dly, Each fireplace should have its grate, on which the fuel must be placed ; and its separate ash-pit, which must be closed by a door well fitted to its frame, and furnished with a register for regulating the quantity of air admitted into the fireplace through the grate. It should also have its separate canal for carrying off the smoke into the chim- ney ; which canal should be furnished with a damper or register : by means of this damper, and of the ash-pit door register, the rapidity of the combustion of the fuel in the fireplace, and consequently the rapidity of the generation of the heat, may be regidated at pleasure. The economy of fuel wUl depend principally on the proper management of these two registers.
- ' 3dly, In the fireplaces for all boilers and stewpans which are more than eight or ten
inches in diameter, or which are too large to be easily removed with their contents by the strength of one hand, a horizontal opening just above the level of the grate must be made, for introducing the friel into the fireplace ; which opening must be nicely closed by a fit stopper, or by a double door. In the fireplaces which are constructed for smaller stewpans this opening may be omitted, and the fuel may be introduced through the same opening into which the stewpan is fitted, by removing the stewpan occasionally a moment or two for that purpose. '■ 4thly, All portable boilers and stewpans, and especially such as must often be re- moved from their fireplaces, should be circular, and they should be suspended in their fireplaces by their circular rims ; but the best form for all fixed boilers, and especially such as are very large, is that of an oblong square ; and all boilers, great and small, should rather be broad and shallow than narrow and deep. A ciiTular form is best for portable boilers, on account of the facility of fitting them to their fireplaces ; and an ob- long square form is best for large fixed boilers, on account of the facility of constructino' and repairing the straight horizontal flues under them and round them, through which the flame and smoke by which they are heated are made to circulate. When lar"e boilers are shallow, and when their bottoms are supported on the tops of narrow flues, the pressure or weight of their contents being supported by the walls of the flues, the metal of which the boiler is constructed may be very thin, which will not onlv diminish very much the first cost of the boiler, but will also greatly contribute to its durability ; for the thinner the bottom of a boiler is, the less it is fatigued and injured bvthe action of the tire, and the longer, of course, it will last ; which is a curious fact, that has hitherto been too little known, or not enough attended to, in the construction of large boilers. " 5thly, All boilers, great and small, should be furnished with covers, which covers should be constructed in such a manner, and of such materials, as to render them well adapted for confining heat. Those who have never examined the matter with attention would be astonished, on making tiie experiment, to find how much heat is carried off by the cold air of the atmosphere from the surface of hot liquids, when they are exposed naked to it, in boUers without covers; but in culinary processes it is not merelv the loss of heat which is to be considered ; a great proportion of the finer and more'rich and savoury particles of the food are also carried off at the same time, and lost ; which renders it an object of serious importance to apply an effectual remedy to this evil." ( Count Rumford's Essays, essay x. p. 28. ) 1484. We have given the five preceding rules in Count Rumford's own words, because they contain the fundamental principles of the construction of stewing-hearths ; because no directions of equal merit have been given since his time ; and because they are as requisite now as when first published, in 1799. 1485. The Covers for Boilers should, if possible, be made of some nonconducting substance : and wood would be the best, were it not for the changes which it is Uablc to
