CHAPTER XXII 
METHODS OF HEATING 
houses very brief reference was made to the 
various methods of heating. It will be well 
to understand a little more in detail how to heat 
glass structures, as temperature is, next to moisture, 
the most important factor of success. If steam or 
hot water is used in the dwelling house and a green- 
house of the lean-to type is used, the problem be- 
comes a very simple one, as additional pipes can be 
run through the greenhouse. But as this advantage 
is not always ready to hand, we will consider the 
heating of an isolated house, and the principles in- 
volved may be adapted to individual needs. There 
are three systems of heating: flues (hot air), hot 
water, and steam — the latter we need not take up 
as it is economical only for larger structures than 
the amateur is likely to have. 
Heating by hot air carried through brick or tile 
flues is the simplest and cheapest method for very 
small houses. The best way of constructing such a 
system is illustrated in the diagram adjoining, which 
shows the flue returning into the chimney (after 
traveling the length of the house and back). This 
167 
T° the foregoing chapter on homemade green- 
