Fort Constitution - 1886 proposed plans

From the National Archives.

A massive earth and concrete barbette battery for fourteen 15-inch Rodman guns, proposed for construction in 1872. Note that Walbach Tower was still allowed to exist. Note also the lines of both the 1808 and 1863 forts, and the temporary 1874 emplacement by the bastion for another 15-inch Rodman gun. The proposed battery was never built, part of the poorly funded Federal "Fourth System" of fortifications.