In 1896–1906 several modern Endicott era coast defense batteries were installed at the fort as part of the Coast Defenses of Portland, which also included Fort Williams, Fort McKinley, and Fort Levett. The star fort was demolished to make room for these batteries. Batteries Kearny and Chase totaled sixteen 12-inch mortars (305 mm) and were completed in 1901. These were named for Brigadier General Stephen W. Kearny of the Mexican–American War and Lt. Colonel Constantine Chase of the Civil War. Originally all sixteen mortars were Battery Kearny, but Battery Chase was named in 1906, with each battery comprising eight mortars. They were followed in 1906 by Battery Rivardi with two "disappearing" 6-inch (152 mm) guns and Battery Mason with one 3-inch (76 mm) gun. Battery Rivardi was named for John J. U. Rivardi of the 1st US Artillerists and Engineers, who served 1795–1802 and worked on the First System forts. Battery Mason was named for Philip D. Mason, an artillery officer killed in the Civil War. Two mortars from Battery Kearny-Chase were moved to West Point in 1911, probably to instruct cadets in their use.