Transactions of the American Society of Civil Engineers, Vol. LXVIII, September 1910: The New York Tunnel Extension of the Pennsylvania Railroad. The East River Tunnels. Paper No. 1159 is a comprehensive and detailed technical account documenting one of the most ambitious and significant engineering projects of the early twentieth century. This volume, authored by Alfred Noble, George S. Webster, and Charles M. Jacobs, presents an in-depth exploration of the planning, design, and construction of the East River Tunnels, a critical component of the Pennsylvania Railroad’s New York Tunnel Extension. The book meticulously chronicles the challenges faced in constructing four parallel tunnels beneath the East River, connecting Long Island City in Queens to Manhattan, and ultimately facilitating direct rail access to the newly built Pennsylvania Station. It delves into the innovative engineering solutions developed to address the unique geological, logistical, and technical obstacles encountered during the project, such as working under high water pressure, managing soft riverbed soils, and ensuring the safety of workers in hazardous conditions. Richly illustrated with diagrams, maps, and photographs, the volume provides readers with a vivid understanding of the construction methods employed, including the use of shield-driven tunneling, compressed air techniques, and the deployment of cutting-edge machinery for the era. The authors detail the organization of the workforce, the sequence of construction operations, and the rigorous safety protocols implemented to minimize accidents and ensure the successful completion of the tunnels. In addition to the technical narrative, the book offers valuable insights into the broader impact of the East River Tunnels on urban transportation, commerce, and the growth of New York City. It highlights the collaborative efforts of engineers, contractors, and laborers, and underscores the significance of the project in advancing the field of civil engineering. This volume stands as an authoritative historical record and a testament to the ingenuity and perseverance of the engineers who transformed the vision of a subterranean rail link into a reality. It remains an essential reference for civil engineers, historians, and anyone interested in the monumental infrastructure achievements that shaped modern New York.