Isaac M . St . John Isaac Munroe St . John ( November 19 , 1827 – April 7 , 1880 ) was a Confederate States Army brigadier general during the American Civil War . He was a lawyer , newspaper editor and civil engineer before the Civil War and a civil engineer after the Civil War . As a civil engineer , he worked for the Baltimore and Ohio Railroad Company ( mainly in Maryland ) and the Blue Ridge Railroad Company in South Carolina before the Civil War . After the war , he worked for the Louisville , Cincinnati , and Lexington Railroad in Kentucky ; the city of Louisville , Kentucky ; and the Chesapeake and Ohio Railway Company ( mainly in Virginia and West Virginia ) after the Civil War . Early life . Isaac M . St . John was born on November 19 , 1827 in Augusta , Georgia . He moved to New York , New York with his parents , Isaac Richards St . John and Abigail Richardson Munroe St . John , and attended Poughkeepsie Collegiate School . He graduated from Yale University in 1845 and became a lawyer . In 1847 , St . John became the editor of the " Baltimore Patriot . " He was a civil engineer with the Baltimore and Ohio Railroad Company between 1848 and 1855 . He then moved to South Carolina where he became a civil engineer and chief of construction for the Blue Ridge Railroad Company between 1855 and 1861 . American Civil War service . Isaac M . St . John began the Civil War as a private in the Fort Hill Guards of South Carolina in April 1861 . By October 3 , 1861 , he was an engineer in the Army of the Peninsula . By April 1862 , he was Brigadier General John B . Magruder ' s chief engineer at Yorktown , Virginia in the Peninsula Campaign with the rank of captain . On April 18 , 1862 , St . John became the Chief of the Bureau of Nitre and Mining , an assignment which he held until February 16 , 1865 . In this position , he produced crucial ordnance supplies , including gunpowder and metals , for the Confederate Army , even as the Union blockade of Southern ports became increasingly effective . Among other things , he found limestone caves containing saltpeter in the southern Appalachian Mountains . He was appointed major , CSA artillery , September 26 , 1862 and lieutenant colonel , CSA , Nitre and Mining Corps , May 28 , 1863 . St . John resigned on January 31 , 1864 because the Confederate Senate accused him of protecting draft dodgers . His resignation was refused and the charge was proven untrue . He was promoted to colonel on June 15 , 1864 . On February 16 , 1865 , by special act of the Confederate Congress , St . John was promoted to brigadier general and was appointed commissary general of subsistence because of his procurement skills . He relieved some supply problems through direct acquisitions but his innovations came too late in the war to make a significant impact . St . John was paroled at Thomasville , Georgia about June 1 , 1865 and was promptly pardoned on June 19 , 1865 , after having taken the oath of amnesty on June 18 . Aftermath . After the war , St . John was chief engineer for the Louisville , Cincinnati , and Lexington Railroad from 1866 to 1869 . Then , he was city engineer for two years with city of Louisville , Kentucky . He became a civil engineer for the Chesapeake and Ohio Railway and ultimately the head of its Mining and Engineering Department . Isaac Munroe St . John died April 7 , 1880 at The Greenbrier at White Sulphur Springs , West Virginia . He is buried at Hollywood Cemetery , Richmond , Virginia .