The image above comes from the incredible forgotten-ny.com site. After viewing the archaeological display from the 9th Precinct I did some follow up research on the Etna Foundry which was located on the LES. Here's part of what I found:
Jacob A. Westervelt: The block bounded by Third, Goerck and Houston Streets and the East River held Jacob A. Westervelt's shipyard. He constructed more vessels of medium tonnage than any builder of his time. He was born in Bergen County, New Jersey, in 1800, and went to sea as a lad of 14, and he made several voyages before settling down to learn shipbuilding. He was apprenticed to Christian Bergh, remaining four years. Without graduating, he undertook the construction of two schooners at Charleston, S. C., with his employer's consent, using negro slaves owned by planters in and about Charleston.
Returning to New York with the completion of the schooners, Westervelt became a partner with Mr. Bergh, continuing the association until Bergh retired in 1835, after having built in 15 years 71 vessels from 450 to 600 tons. Westervelt designed and built in connection with Edward Mills, the steamships Washington and Herman, pioneer American ocean liners. Franklin and Havre were the first steam vessels for the Havre Line, followed by Arago and Rhode Island for the Government. Eagle and Morro Castle were built for Spofford Tileston & Company, and Westervelt had great pride in having built the clippers N. B. Palmer and Sweepstakes. For American and foreign governments Westervelt built many vessels, amongst these the frigate Hope, 2,000 tons, in 1825, for the Greek Government; Guadalquiver for Spain; Eusiyama for Japan, and Ottawa, Atsego, Kankakee and the sloop-of-war Brooklyn for the United States Navy. Admiral Farragut declared Brooklyn to be the most efficient man-of-war in the American Navy and it had a splendid record in the Civil War. Jacob A. Westervelt received high political honors and was Mayor of New York in 1852. With his son, Daniel D. Westervelt, he built 50 steamships, 93 ships, 5 barks, 14 schooners, one sloop, two lightships, 11 pilot boats, a total of 181 vessels of 150,624 tons.