ECONOMY OF FUEL. 323 



expedition if required, and if the notches forming the 

 rack, are clofe together the fpace of opening for the 

 draught may be more nicely adjufted. 



The back and cheeks of the fire-place may be made 

 hollow, yet ftrong, by alternately butting againfl: the 

 wall, in what is termed by the bricklayers, fiemijh bond, — 

 and a fmall hole made near the hearth of this hollowed 

 way, communicating to the external air if convenient, if 

 not, a hole may be made near the floor within the cham- 

 ber, and other openings made in any convenient places 

 higher than the opening of the fire-place, to let the heat- 

 ed air pafs from the back or inner part of the brick work 

 into the chamber. 



The conveniencies of this fire-place, are, that the fire 

 may be kindled quickly, and after it burns freely, the 

 valve or damper being lowered, leaving only an open- 

 ing fufficient to carry off the fmoke, which in a well con- 

 firudled chimney may generally be clofed to an inch and 

 half or two inches, but little heat will efcape in the throat 

 of the fire-place. 



If the chimney is fubje<3; to fmoke, it is an eafy ex- 

 pedient to lower the fliding-mantlc fo as to increafe the 

 draught. 



But the fafety from the dangers of fire with this fire- 

 place is not of the leaft importance, for whatever fire is 

 left in the place at night, v.ith the valve clofe Ihut, and 

 the fliding-mantle lowered to join the hearth, the fire 

 will be fmothei"ed. In like manner if by accident the 

 foot takes fire in the flue of the chimney, no alarm fol- 

 lows, as it may inflantly be extinguifhed. 



The lafl improvement which has been made, is to re- 

 medy the evil of the fmoke, paffing between the Aiding 

 mantle and breaft work and efcaping through the crevices 

 round the mantle piece. 



A hole 



