604 



THE NATIONAL GEOGRAPHIC MAGAZINE 





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One man with one metal cutting machine, equipped with tungsten "high-speed" steel 

 tools, can now do as much work as could live men with rive machines equipped with the 

 carbon steel tools formerly used. These wonderful alloy steels, containing six or seven 

 metals, have been largely, though not wholly, developed in the United States. 



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POPULATION OF THE 

 UNITED STATES 



TOTAL COAL MINED IN THE 

 UNITED STATES PRIOR TO 1^13 



1313 PRODUCTION 



B13 PRODUCTION 



COAL RESERVE 



IN THE 

 UNITED STATES 



POPULATION OFWEWOffLD 

 OUTSIDE OF THE 

 UN/TED STATES 



TOTAL COAL MINED IN TME WORLD- 

 OUTS IDE, OF THE UNITED STATES 

 PRIOR TO ISO 



COAL RESERVE 



IN THE 

 WORLD OUTSIDE 



OF THE 

 UNITED STATES 



COAL 



RESERVES AND PRODUCTION IN THE UNITED STATES COMPARED WITH THE 

 REMAINDER OE THE WORLD 



