250 W. 0. DUNTLEY 



boiler making or ship building, the pneumatic tool is also in 

 evidence; take the construction of a modern steel sky scraper, 

 or descending to the less elevated but eventually more use- 

 ful structure, the rapid transit subway tunnel, and your 

 ears will be struck with the rumbling noise of the hand pneu- 

 matic tools such as hammers and riveters, permanently 

 uniting the various elements which go to make up such a 

 structure. 



The arduous work of removing rust from plates or col- 

 umns, either by pickling in acids, scouring with stone or 

 chipping away with hammer and chisel, is now better done, 

 in one tenth of the time and with one fourth the labor with 

 a pneumatic tool using a blast of sand. Boiler tubes are 

 expanded with a pneumatic roller. The fins on large castings, 

 such as fly wheels, columns, pulleys, statues, and what not, 

 are chipped away with pneumatic tools. Not only in the 

 ironworker's hands do these tools prove ready servants, stone- 

 masons, architectural stonecarvers, granite facers find them 

 the most serviceable tools ever invented. These tools have 

 simply to be held up to the work while the oscillating or recip- 

 rocating piston within, which performs the function of the 

 hammer set in motion by the compressed air, does the rest. 

 Woodworkers make use of them for boring, turning, mortising 

 and any class of work where the brace and bit or hammer and 

 chisel have hitherto held undisputed sway. The painters' 

 trade, too, has been invaded by the so-called air brush, which, 

 as we understand it, is not a brush at all, at least, not made 

 of bristles. With this pneumatic tool, freight cars, their 

 running gear, dwellings, barns, outhouses (inside and out), 

 chicken coops, poultry houses, long stretches of surface like 

 fences, the street railway tunnel, the elevated structure, 

 the viaduct at One Hundred and Fifteenth street, New York 

 • — any surface, in fact, to be coated with plain colors, may be 

 covered. 



There is scarcely a mechanical trade in which these 

 tools are not now used for one or more processes. It would 

 hardly be possible to give a complete list of the tools invented 

 for and applied to this purpose — in fact, their number is legion 

 and they are increasing every day. 



