Transactions of the American Society of Civil Engineers, Vol. LXVIII, Sept. 1910: The New York Tunnel Extension of the Pennsylvania Railroad.: The Cross-Town Tunnels. Paper No. 1158

Published in September 1910, 'Transactions of the American Society of Civil Engineers, Vol. LXVIII' features a detailed examination of the New York Tunnel Extension of the Pennsylvania Railroad, authored by James H. Brace and Francis Mason. This scientific publication addresses the engineering and construction challenges faced during the tunnel's development, including excavation methods, contract processes, and innovative techniques like top heading and bench methods. The work is notable for its in-depth technical descriptions and illustrations, showcasing the complexities of urban tunnel construction in the early 20th century.