At the Battle of Peachtree Creek, he prevented a dangerous Confederate movement against Sherman and his rapidly constructed works allowed him to turn back the Confederate thrust, a victory that put his official military career back on track. After the capture of Atlanta, Newton left active field duty and commanded the District of Key West and the Tortugas of the Department of the Gulf from 1864 to 1866. His last campaign resulted in a defeat at the Battle of Natural Bridge in Florida in March 1865, which temporarily enabled the Confederates to hold on to the state capital. Postbellum career Returning to the Corps of Engineers, Newton oversaw improvements to the waterways around New York City, into Vermont, and to the Hudson River above Albany. He also had charge of New York Harbor defenses until he was appointed Chief of Engineers in 1884. He is famed for blowing up two of New York's Hell Gate Rocks, the three acre Hallet's Point Reef with 50,000 pounds of a nitroglycerine compound and the nine acre Flood Rock with 282,730 pounds of dynamite on October 10, 1885, that detonation destroying 730,935,900 pounds of rock. For his extraordinary achievements, he was elected to the prestigious National Academy of Sciences. Newton retired from the Army in 1886 after forty-four years of service, a year short of mandatory retirement at age 64. He served as Commissioner of Public Works, New York City (1886–88), and as President of the Panama Railroad Company (1888–95). Newton died in New York City on May 1, 1895 of complications from heart disease and rheumatism. He was buried at Calvary Cemetery in Woodside, Queens on May 4, 1895 and then reburied at West Point on June 14, 1895. In 1886, he was awarded the Laetare Medal by the University of Notre Dame, the oldest and most prestigious award for American Catholics. Newton had converted to Catholicism from Protestantism. In 1899, the Corps of Engineers named a 175-foot paddlewheeler in Newton's honor; the boat was later used as the Minnesota Centennial Showboat until its destruction by fire in 2000. See also List of American Civil War generals (Union) References Forthcoming book from McFarland about Hell Gate and John Newton in 2020 written by Thomas Barthel. Eicher, John H., and David J. Eicher. Civil War High Commands. Stanford, CA: Stanford University Press, 2001. . Biographical sketch in The Popular science monthly 1886 Art. 4.