He pursued a civil engineering career in a peacetime and became in 1893 the first head of the Office of Road Inquiry, which was the Federal Highway Administration's predecessor.

[2][3] Stone served as a Union Army officer during the Civil War and became noted for his stubborn defense of the McPherson Farm during the Battle of Gettysburg.

On July 1, 1863, on the first day of the Battle of Gettysburg, his brigade, largely composed of green troops, was posted on McPherson's Ridge south of the Chambersburg Pike.

Stone moved his regiments to block attacks by Colonel John Brockenborough and Brigadier General Junius Daniel.

[5] After his return to active duty, Stone served briefly as a brigade commander in James Wadsworth's 4th Division, V Corps during Lt. Gen. Ulysses S. Grant's 1864 Overland Campaign.

Volunteers, to rank from September 7, 1864, for "gallant services during the war, and especially at Gettysburg" and the United States Senate confirmed the appointment on February 20, 1865.

[10][11] Stone briefly returned to active military duty with the rank of Brigadier General in 1898, serving in the Puerto Rican Campaign of the Spanish–American War.