Civil War Union Brevet Brigadier General. Born to a wealthy family in Prattsburg, New York, he received local schooling and attended Union College in Schenectady, New York. Upon his graduation in 1856, he managed his father's estates in Sheffield and Warren Counties. At the outbreak of war, he joined the 13th Pennsylvania Reserves, commonly known as “The Bucktails”, with the rank of Major, and led the regiment in the June 1862 Seven Days' Battles. Later, he was promoted to Colonel and given command of the 149th Pennsylvania Volunteer Infantry, with orders to join in the defenses of Washington. On February 16, 1863, he was given command of the 2nd Brigade, 3rd Division, I Corps, Army of the Potomac, leading it at May 1863 Battle of Chancellorsville and on the first day of the Battle of Gettysburg (July 1, 1863), where he was severely wounded in the arm and hip in the action near McPherson Barn west of the town. Captured and then paroled, he returned to duty on October 31, 1863, and was assigned to Washington DC as President of Court Martial. He remained in this position until March 23, 1864, when he returned to duty in time to command the 3rd Brigade, 4th Division, V Corps, Army of the Potomac, at the May 1864 Battle of the Wilderness. Here, on the second day of battle, he was seriously injured when his horse fell on him. On September 7, 1864, he was made commander of the volunteer depot at Camp Curtin, Pennsylvania. This command lasted until December 15 of that year, when he was assigned command of the prison at Alton, Illinois. He resigned his commission on January 27, 1865, having been brevetted Brigadier General, US Volunteers on September 7, 1864 for “gallant and meritorious services during the war, and especially at Gettysburg”. In civilian life he referred back to his love of engineering, and was connected with many important engineering works including the blowing up of the Hell Gate rocks and the removal of the bars from the harbor of New York City, New York. He also had an interest in mass transit and invented a form of elevated railway that was displayed in Philadelphia, Pennsylvania during the 1876 Centennial Exposition. He also was known for his invention of a suction dredge for harbor work. He later turned his attention to improving roads especially in New Jersey, which due to his efforts had some of the finest roads in the country at the end of the 1800s. Heeding the call of his country once more, with the rank of Brigadier General and Chief of Engineers, he served on the staff of General Nelson Miles during the Spanish-American War. Leading cavalry in Puerto Rico, he captured several cities. His service there led to his love of the island and after the war ceased, he worked very hard to assist in the development of the island. In 1900, he was given a unique tribute as a species of royal palm, was named in his honor, the Roystonea Regia. He later served as Chief Engineer of the Union Terminal Company in New York City. He died in Mendham, New Jersey, from what many including his wife thought was some sort of disease he had contracted while in Puerto Rico. Among the many tributes that were shown to him was a large wreath from President and Mrs. Theodore Roosevelt, which was placed on the coffin and was buried with him. Stone Avenue at Gettysburg National Military Park is named in his honor.