THE MODERN SKYSCRAPER 



rule, counter-pressure being made by a man holding 

 a sledge against the end of the rivet opposite the 

 riveter. 



The efficiency of this hammer depends upon the 

 number, rather than the force, of the blows struck, 

 and may be utilized for many other purposes besides 

 riveting, such as hammering and calking. Similar 

 hammers are also used for chiselling, and have revo- 

 lutionized stone carving, taking the place of the chisel 

 and mallet of the old-time carver. Machines for this 

 purpose give very light but rapid strokes as high as 

 15,000 blows a ninute so rapid indeed that the sound 

 made is a continuous buzz in place of the rapid, inter- 

 rupted tapping of the riveting hammer. The carved 

 stone-work of the steel-frame buildings is often made 

 with these tools after the roughly cut stone is in place 

 on the building. 



There are great numbers of pneumatic tools having 

 a rotary motion adapted to various kinds of boring 

 and drilling machines, both for wood and metal work- 

 ing. These are, of course, used in innumerable ways 

 in building construction, although seen less frequently 

 than such tools as the pneumatic riveter because their 

 use is often confined to factories. 



The modern steel-frame structures, perhaps the most 

 beautiful examples of which are represented by Ameri- 

 can hotels and apartment houses, are frequently 

 spoken of as "palaces." Save for the fact that they 

 are not the residences of crowned heads, the term is not 

 inappropriate. For many of them are quite as large, 

 and far more magnificent in their appointments than 



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