Many of the ordinary types of steam boilers are used for steam heating and in addition to these there is a cast iron sectional boiler which is used for dwelling houses to a great extent. (Fig. 64.) The main thing is to select some well-known type and to see that it is carefully set, with all attachments, which will usually be described in the contracts. This method of direct radiation lacks the advantage of the introduction of fresh air into the house, but, if care is taken to provide for this by other means, it is economical and positive in its action. The main point to be seen is that heater, pipes and radiators are amply large, and that the radiators are well placed and supplied by carefully graded pipes, tightly and neatly connected. Cellar pipes should be covered with some of the patented sectional pipe coverings, and radiators and all pipes which are exposed to view may be coated with bronze of a desired color. Where pipes pass through floors or partitions they should be protected by sleeves three-quarters of an inch larger than the pipes, and collars should be neatly placed around the pipes at the floor and ceiling, or on each side of the partition

Fig. 62. Cast Iron Radiator.

Fig. 62. Cast-Iron Radiator.