72 THE SMALL COUNTRY PLACE 



Most of the modern cast-iron boilers used for house 

 and greenhouse heating are made in sections, so that a 

 small number of sections are used for small buildings 

 and more are added for larger ones. Another advantage 

 claimed for sectional boilers is that if one section cracks 

 or is in any way defective it can be replaced without 

 buying an entire new boiler. 



Steam Heat. 



Where a large amount of heat is required steam is, 

 however, very satisfactory. If a small amount of heat 

 is needed it can be obtained only by running steam 

 through a small number of pipes. No heat can be 

 circulated in the pipes until the water gets above 212, 

 and all heat is lost when it falls below this. The cost 

 of piping for steam heat is less than that for hot water. 



With steam and hot-water heating no provision is 

 generally made for introducing fresh air into the rooms. 

 But if the building is loosely built or ventilation is pro- 

 vided for by an opening into the chimney near the 

 floor, the foul air will be rapidly replaced by that from 

 outside. 



