Editing Fort Hamilton (section)

===Civil War===
{{Main|New York in the American Civil War}}
During the Civil War, Fort Hamilton's garrison expanded. A ship barrier across the Narrows assisted Fort Hamilton and its sister forts on [[Staten Island]], now called [[Fort Wadsworth]], in protecting the harbor against the possibility of [[Confederate States of America|Confederate]] raiders. The forts also provided troops to help put down the [[New York Draft Riots]] of 1863. Fort Hamilton also served as a [[prisoner-of-war camp]], and an exterior "New Battery" of guns was added.<ref name=NAForts1>[http://www.northamericanforts.com/East/nycity3.html#harbor Fort Hamilton at American Forts Network]</ref>

Rifled cannon made vertical-walled masonry fortifications obsolete during the [[American Civil War|Civil War]]. The first response of the US coast defense forces to this was a series of new batteries, with guns in open positions behind low earth walls and brick magazines with heavy earth cover between the guns. Most of these were located near existing forts. In 1871 construction began at Fort Hamilton on an 8-gun water battery and a 15-gun mortar battery, but the latter was never completed or armed.<ref name=NAForts1/> Money for these projects ran out in the late 1870s, and US coast defense languished, with few improvements completed for nearly 20 years.