254 Prof. Hosking on Ventilation. 
room; and if the opening over the fire to the flue be reduced to 
the real want of the fire, the consumption of air by the fire will 
not be so great as may be supposed, and there will remain a 
supply of tempered air waiting only an inducement to enter for 
the use of the inmates of the apartment. An opening directly 
from the room into the flue upon which the fire is acting with a 
draught more or less strong, ata high level in the room, will 
afford this inducement; it will allow the draught in the fiue to 
act upon the heated and spent air under the ceiling, and draw it 
off; and in doing so will induce a flow of the fresh and tempered 
air from about the body of the grate into the room. 
_ The mode thus indicated of increasing the effect of the famil- 
lar fire, and making it subservient to the important function of 
free and wholesome ventilation, is not to be taken as a mere sug- 
gestion, and now for the first time made. It has been in effec- 
tive operation for six of seven years, and is found to answer well 
with the simple appliances referred to. But it is the mode and 
the principle of action that it is desired to recommend, and not 
the appliancess, since persons more skilled in mechanical con- 
trivances than the author professes to be, may probably be able 
necessary to leave the same space open over the fire after the steam 
and smoke arising from fresh fuel have been thrown off, as may 
be necessary immediately after coaling. The opening by the 
register valve into the flue may be reduced when the smoke has 
been thrown off, so as to check the draught of air through the 
fire, and greatly to increase the draught by the upper opening 
into the flue, to the advantage of the ventilation and to the sav- 
ing of fuel, while the heat from the incandescent fuel will be 
thereby rather increased than diminished. 
Moreover the system being applicable in the cottage of the la- 
borer, as fully and easily as in the better appointed dwellings of 
those who need not economize so closely as laboring people are 
obliged to economize, the warmed air about the grate in a lower 
room may be conveyed directly from the air-chamber about the 
meee ia A eee 
* The appliances used by Mr. Hosking wi , ibed in his 
“ Healthy ys a published by eden iedvenscolienams — ue 
