Before Inwood and Washington Heights were densely populated and long before the Henry Hudson Bridge stretched across the Hudson, the Johnson Family built their ironworks in the Spuyten Duyvil.
Having first worked upstate as part of another firm, Elias Johnson had made a fair amount of money creating munitions and provisions for the Mexican American War. Ready to strike out on his own, Johnson raised some capital and began building his factory in Spuyten Duyvil in 1853 with his son Isaac. Nor was Isaac a neophyte, he had graduated from Rensselaer Polytechnic Institute that same year with a degree in Civil Engineering.
It was Isaac Johnson who sited the mill, scouting locations throughout the city (including what is now Central Park.) Eying the peninsula jutting out from Spuyten Duvel, Johnson decided to put the foundry there with the land being shared by a rolling mill. The proximity to the railroads and New York's waterways made the plant quickly prosperous. Soon it was pushing out ironwork for all manner of commercial and home applications.
The Johnsons soon were able to afford fancy homes, expensive lifestyles, and trips to exotic locales. However, their prosperity was only beginning. During the civil war, the Johnsons built prototypes of a cannon for the Union, guaranteeing their quality. Its success made the Johnson Foundry an important munitions supplier, a role the foundry would continue in through World War I. It would also branch out into steel production as well as automobile mechanics (dominating the automobile parts industry in its nascent stages.)
As the prospects of the foundry grew so did the number of their employees, starting in the low hundreds to over sixteen hundred employees at the time of its closing. The Johnsons, a fairly religious family, were said to be fairly interested in the well being and health of their workers and built a number of reading rooms, chapels, and accommodations for their workers.
The end would come, not from depression or disaster, but the New York Legislature. In 1919, it was decided that the ship canal would be straightened to make it more navigable. Peninsulas like the one that the Johnson Foundry were situated on were to be blasted away and dredged. It would take four more years, but the Johnson foundry would be closed and demolished.