130 nOT-HOUSE. 
Furnace and Flues. — It is of great importance to have 
these erected in such a manner as will effectually heat the 
house. The greatest difficulty is to have the furnace to draw 
well. As workmen are not generally conversant on the sub- 
ject, nor yet understand the effect or distribution of heat in 
these departments, we will give minute details on their con- 
struction. The furnace should be outside of the house, 
either at the back or end ; the former is preferable, circum- 
stances not always allowing it on the other plan. Dig out the 
furnace-hole, or what is termed stock-hole, about five feet deep. 
Let the door of the furnace be in the back wall of the house, 
thereby having all the heated building inside, that no heat 
may be lost. The brick-work round the furnace should be 
nine inches thick, laying the inside with fire-brick. Around 
the outside leave a vacuum two or three inches wide, to allow 
the heat to arise from around the furnace into the interior of 
the house, thereby saving the whole heat of the fuel. The 
furnace will require to be two and a half feet long, ten inches 
wide, and one foot high, before the spring of the arch and 
clear of the bars ; leave one foot for an ash-pit, then lay the 
hars. They should be sixteen inches long, one inch broad 
on the upper side, two inches deep, and two-eighths broad on 
the lower side, and, with the door and frame, should be cast 
iron. Half an inch between each bar will be sufficient. The 
flue should rise from the furnace by a steep declivity of from 
twenty inches to two feet, and pass the door of the house 
(without a dip), when it must be elevated above the level of 
the floor of the house along the front, and at the opposite 
end of the house must dip to pass the door. The dip must 
not be lower than the bottom of the flue at the neck of the 
furnace. Lead it along the back to enter the wall over the 
furnace. When thus taken round the house, the heat will 
be expanded before it enters the chimney. The inside of 
the flues should be from six to ten inches wide, and eight 
inches deep ; plaster the bottom of it, but no other part, as 
plaster is partially a non-conductor. The above description 
is for burning anthracite coal ; but where wood is to be the 
fuel, the furnace must be one-half larger. We have been 
particular in the description of furnace bars, as those gene- 
rally used are miserable substitutes. Circumstances may 
cause the furnace to be placed at the end or front of the 
house. In either case, the stock-hole will not rcrpuire to be 
