which these pieces were put together have to be fol- 

 lowed in exact rotation in every instance. Foundation 

 stones did not necessarily precede the masonry of the 

 upper stories once the steel frame was up, as was nec- 

 essary in the older form of construction. As the 

 masonry of each story rested on steel supports it was 

 now possible for the masons to begin, literally, at the 

 top stories and build the walls of the upper stories 

 first, or to work on the walls of several different stories 

 at once. Indeed it was not an uncommon sight to 

 see a tall building in the course of erection in which 

 the masons were laying the walls of several stories 

 simultaneously. 



In these new buildings the modern architects had 

 to meet certain conditions and solve certain problems 

 that would have puzzled the builders of a century ago. 

 Among these was the question of heating and fire- 

 proofing. Elsewhere a description of this fire-proofing 

 is given ; the problem of heating was a relatively simple 

 one, thanks to the application of steam and hot water. 



THE PROBLEM OF HEATING 



Like many other anomalies in the progress of civi- 

 lization hot-water heating represents one of the oldest 

 as well as the newest methods of heating buildings. 

 At the very time when the ancient Greeks were heat- 

 ing their houses with open fires, the smoke from which 

 made its exit through a hole in the roof like the fire 

 in an Indian tepee since the Greeks were not familiar 

 with chimneys their neighbors, the Romans, were 



[166] 



