=64. Dimensions and Capacity of Chimneys.= Nearly all the factory
buildings combine in their structure a power plant, not the least
important feature of which is the =chimney=. There are two things to
consider in the design of a power chimney—first, its capacity for
providing the necessary draft and the conduction of the requisite
volume of gases from the furnace or boiler, and second, its stability.
The first requirement regulates its diameter and height, and these
dimensions, together with its construction, determine also its
stability.