A brief spurt of enthusiasm for upgrading US fortifications took place in the 1870's, when someone noticed that the powers of Europe had been advancing in military technology since the US Civil War, while the US had not. The North Battery, emplacements for five big guns to defend the Thames River, was built in 1875 and 1876.

Did I mention that this enthusiasm for postwar fortification was brief? By the time the emplacements for these guns were complete, money and interest for the project had run out. Fortification upgrades all along the east coast of the US were put on indefinite hold.

In the 1890's, three 15" Rodman Guns were finally installed at the North Battery. The Rodman was seen as a viable seacoast defense weapon into the early 20th century, but it was vastly outclassed in range and destructive power by guns being produced in Europe.

We're looking here at one of the gun emplacements of the North Battery, incidentally.