Transactions of the American Society of Civil Engineers, Vol. LXVIII, September 1910: The New York Tunnel Extension of the Pennsylvania Railroad, Paper No. 1150 is a comprehensive and authoritative technical report detailing one of the most ambitious and significant engineering projects of the early twentieth century. Authored by Alfred Noble, George S. Webster, and Clinton L. B. Fish, this volume meticulously documents the conception, design, and construction of the Pennsylvania Railroad's monumental tunnel extension into New York City-a project that forever transformed the city's transportation infrastructure and set new standards in civil engineering. The book provides an in-depth exploration of the challenges faced in constructing the tunnels beneath the Hudson River, Manhattan, and the East River, connecting New Jersey and Long Island with the heart of New York City. It covers the innovative engineering solutions developed to address complex geological conditions, the use of cutting-edge tunneling shields, and the implementation of advanced ventilation and safety systems. Detailed descriptions of the methods used for excavation, lining, and waterproofing the tunnels are accompanied by technical drawings, diagrams, and photographs that illustrate the scale and intricacy of the work. In addition to the technical aspects, the volume discusses the logistical and organizational efforts required to coordinate thousands of workers, manage materials, and maintain safety standards throughout the multi-year construction process. The authors also examine the broader impact of the tunnel extension on urban development, commerce, and the daily lives of New Yorkers, highlighting the project's role in shaping the modern metropolis. Rich in historical context and technical detail, this book serves as both a valuable reference for engineers and a fascinating account for anyone interested in the history of New York City, the Pennsylvania Railroad, or the evolution of large-scale infrastructure projects. It stands as a testament to the ingenuity, perseverance, and vision of the engineers and workers who brought the New York Tunnel Extension to life.