Chicago : Engineering and Contracting Pub. Co. · leaf 194
he attendantcosts correspondingly high for as the depth in-creases the wage per shift increases and thelength of shift decreases. The limit for pneu-matic sinking is about 100 ft. below waterlevel, for few men can stand the air pressurenecessary to overcome the head of the waterat this depth. The… … _ShaftBsr. Rock Drill Fig. 1—Method of Sinking Concrete DropShaft. Fig. 2—Method of Sinking PneumaticCaisson. Fig. 3—Method of Sinking Shaft in Rock. any carpenter or blacksmith can duplicate.The forward wheels, E, are double and aremade of two mine car wheels set face to face.The rear truck is…
Buildings
Internet Archive · University of Illinois Urbana-Champaign · Public Domain Mark 1.0. Free to use for anything.
