DescriptionDigital image of Hudson & Manhattan R.R. postcard titled: The masters of industry who built the tunnels, 1908. Courtesy of Leon Yost. A photo view inside a tunnel with men seated at the left on several open passenger cars and others standing on the tunnel floor. Note there are two sets of narrow guage track laid. The person at the left (hand on the brakes) appears to be chief engineer Charles M. Jacobs. The other men are all in business dress and are not identified. From a series: The Hudson and Manhattan Railroad Company Tunnel (McAdoo system) under the Hudson River.