What tunnel runs under the Hudson River and has a ventilation system innovated by Ole Knutsen Singstad?
Ole Singstad Ole Knutsen Singstad (June 29, 1882 – December 8, 1969) was a Norwegian-American civil engineer who innovated the ventilation system for the Holland Tunnel (which subsequently became commonly used in other automotive tunnels) and advanced the use of the "Sunk-tube" method of underwater vehicular tunnel building, a system of constructing the tunnels with prefabricated sections.
58 Joralemon Street 58 Joralemon Street, in Brooklyn Heights, Brooklyn, New York, United States, is a Greek Revival structure built in 1847 as a private residence, but is now a New York City Subway vent. The property was acquired by the Interborough Rapid Transit Company in 1908, who gutted the interior and converted the structure to "the world’s only Greek Revival subway ventilator". The ventilator also serves as an emergency exit from the eastern end of the New York City Subway's Joralemon Street Tunnel, which carries the IRT Lexington Avenue Line ( trains ) between Bowling Green and Borough Hall, where it becomes the IRT Eastern Parkway Line ( trains ).