Figure 12. — Works at the central shaft, Hoosac Tunnel, for hoisting, pumping and air compressing 

 machinery, and general repair, 1871. {Photo courtesy of State Library. Commonwealth oj Massachusetts.) 



214 



igure rj. I li m >s M : 1 1 \\i 1 . Air-compressor bi elding on I toosic River near North Adams- I he < ompressors 

 were driven partially by waterpower, derived from the river. {Photo courtesv of State Library, Commonwealth 



qj Massachusetts.) 



I'.tl.LETIN 240: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 



