Figure 39. Haskin's pneumatically driven tunnel under the Hudson River, 1880. In the 

 engine room at top left was the mai hinery for hoisting, generating ele< tricky l"t lighting, 



and air compressing. The air lock is seen in the wall of the brick shall. Mill model — 

 0.3" scale. (Smithsonian photo 49260.) 



Figure 4. 



MINI RS escaping into the air lock dining the blowout in Haskin's tunnel. 



PAPER 41: TUNNEL ENGIN1 I RING A Mi 51 I M ikl \l\ll \l 



233 



