94 THE HOT-HOUSE. [Jan. 
flues, which will afford an additional advantage in more efiectually 
diffusing the whole heat internally in the house, much of which 
would be lost in the back wall were the flues attached to it: the first 
range may be carried along the front and both ends, dipping under 
the end door-ways and rising the other side; if there is no return 
flue to be in front, which is not necessary in a house of moderate 
dimensions, let this flue be carried so that the covering tiles and 
plaster may be within three inches of the level of the front and 
end walls, upon which a board maybe supported with bricks, to be 
brought on an exact level with the front wall, for the convenience of 
placing thereon a number of pots of strawberries, for forcing, or any 
other small plants; and, moreover, the flue being carried near the 
glasses, the heat will be particularly efficacious in repelling the cold 
external air, frost, damps, &c., and also in distributing the heat more 
equally to all parts of the house: for the several returns in the 
back wall will counterbalance the strong heat discharged by this 
first range where most wanted. 
The first range being continued round the front and ends, must 
then be caried along the back wall in four or six returns, which 
will be sufficient to expend all the heat before its discharge into the 
chimney, which must be carried up immediately from the end of 
the uppermost or last flue, either in or outside of the back wall, so 
as not to appear in the inside of the house, and particularly in the 
opposite end of the fire-place. 
The under range of flues immediately communicating with the 
fire ought to be four bricks on edge deep, that they may not be too 
soon stopped with the soot, and all the flues eight inches in the clear 
and covered with broad tiles; the several returns may be made three 
bricks on edge deep; and in the beginning of the first bottom flue 
you may have a sliding iron regulator, to use occasionally in admit- 
ting more or less heat, as it may seem necessary; being very 
careful as you proceed that the brick work of each flue be care- 
fully jointed with the best mortar for that purpose, and well pointed 
within that no smoke can get out, having each return closely 
covered with broad tiles well bedded and jointed with mortar, cover- 
ing the uppermost flues also with broad thick tiles the whole width, 
all very closely laid and joined as above, and the said uppermost or 
last range of flues to terminate, as before observed, in a vent or 
chimney atone end of the back wall; or if two separate sets of 
flues, a chimney at each end in which you may contrive an iron 
slider near its communication with the last flue, to confine the heat 
more or less on particular occasions, or to prevent its passing off* 
too quickly, or becoming of too weakly a degree. 
In very wide stoves flues are continued immediately round the 
bark pit within an inch or two of the wall, to form a vacancy for 
the heat to come up more freely, and also to prevent its drying the 
tan of the bark-bed too much, which flues may be used occasionally 
or generally by the assistance of a sliding iron regulator, to admit 
or exclude the heat less or more as it may appear expedient. 
You should be very careful that neither the fire place nor flues 
