Transactions of the American Society of Civil Engineers, Vol. Lxviii, Sept. 1910the New York Tunnel Extension of the Pennsylvania Railroad.the North River Tunnels. Paper No. 1155

This is a primary technical document from September 1910, presenting the designs, construction methods, and field conditions encountered during one of the early 20th century's most ambitious infrastructure projects. The paper, authored by B.H.M. Hewett and W.L. Brown, documents the North River Tunnels - the railroad tunnels that carry trains beneath the Hudson River between New York City and Weehawken, New Jersey, delivering passengers directly to Penn Station. Organized into four sections covering Shafts, Plant, Land Tunnels, and River Tunnels, the document offers a comprehensive technical account of how engineers overcame extraordinary geological and logistical challenges at a time when tunneling beneath a major river was still a daring endeavor. For readers interested in the history of engineering, American infrastructure, or the development of New York City's transportation network, this paper provides an invaluable firsthand account from the engineers who built it. While dense and technical in nature, it captures a transformative moment in civil engineering when tunnel-boring technology and construction methods were being pushed to their limits. It stands as a testament to the ambition and problem-solving that connected Manhattan to the New Jersey mainland by rail.