and the Economy of Fuel. 35 



is no longer an occasion for it ; for, upon closing them 

 both entirely, the fire will be immediately extinguished, 

 and the half-consumed fuel, instead of being suffered to 

 burn out to no purpose, will be saved. 



Nearly the same effects as are produced by a damper 

 may be produced without one, by causing the smoke, 

 after it has quitted the fire-place, to descend several 

 feet below the level of the grate on which the fuel is 

 burned before it is permitted to go up the chimney. 



There is another circumstance of much importance 

 which must be attended to in the construction of fire- 

 places, and that is, the proper disposition of the fuel ; 

 for in order that the combustion may go on well, it is 

 necessary not only that the fuel be in its proper place, 

 but also that it be properly disposed ; that is to say, 

 that the solid parts of the fuel be of a just size, and 

 that they be not placed too near each other, so as to 

 prevent the free passage of the air between them, nor 

 too far asunder ; and if the fire-place can be so con- 

 trived that solid pieces of the inflamed fuel, as they go 

 on to be diminished in size as they burn, may naturally 

 fall together in the centre of the fire-place without any 

 assistance, it will be a great improvement, as I have 

 found by experience. This may be done, in small fire- 

 places (and in these it is more particularly necessary), 

 by burning the fuel upon a grate in the form of a seg- 

 ment of a hollow sphere, or of a dish. (See the Figures 

 3 and 4, Plate I.) All those I now use, except it be for 

 fire-places which are very large indeed, are of this form ; 

 and where wood is made use of for fuel, it is cut into 

 small billets from 4 to 6 inches in length. Instead of 

 a grate of iron, I have lately introduced grates, or rather 

 hollow dishes or pans of earthen-ware, perforated with 



