Fourteen Foot Bank Light - Credit: Wikimedia Commons
Fourteen Foot Bank Light is a lighthouse in the Delaware Bay near Bowers Beach, Delaware. Built in 1885–1886 at the south end of Joe Flogger Shoal, it was the first lighthouse to be built using a pneumatic caisson. The wooden caisson structure was excavated to a depth of below the seabed, then filled with of concrete. A cast-iron base was meanwhile erected on the caisson as it sank. A house-like structure was built on top of the base, designed by H.A. Ramsay and Son of Baltimore. Engineers for the structure were Anderson and Barr, and the contractor was D.P. Heap. Read more on Wikipedia
Source: en.wikipedia.org