2007-01-032022-02-032007-01-032022-02-03http://hdl.handle.net/11124/6945Date scanned: 2002-.USBM #H-77878-P; Figure 13 Typical bolted roof section after Guniting. View is upward along line of tunnel. Ventilation pipe is wired to mine tie.Held in the Russell L. and Lyn Wood Mining History Archive, Arthur Lakes Library, Colorado School of Mines.Donor: United States Bureau of Mines.Guniting refers to the pneumatic application of portland cement mortar (gunite). Spraying gunite on the rock surface with a cement gun was done to improve support, make a smooth surface for air currents, and prevent weathering of the rock. This image may depict the construction of tunnels for New York City's water supply from the Catskill watershed. In 1905 the New York State legislature passed an act allowing the City to acquire lands and build water control structures in the Catskills for its water supply, including the East Delaware Tunnel, West Delaware Tunnel and the Rondout Tunnel (Delaware Aqueduct).Rights management statement available at: http://library.mines.edu/digital/rights.htmlScenes, undergroundTunnels and tunnelingStillImage