Henry Pleasants " For the English music critic Henry Pleasants , see " Henry Pleasants ( music critic ) . Henry Clay Pleasants ( February 16 , 1833 – March 26 , 1880 ) was a coal mining engineer and a brigadier general in the Union Army during the American Civil War . He is best known for organizing the building of an underground tunnel filled with explosives under the Confederate lines outside Petersburg , Virginia , resulting in the Battle of the Crater on July 30 , 1864 , an opportunity for Union troops to break the defense of Petersburg . Early life and career . Pleasants was born in Buenos Aires , Argentina , and did not live in the United States until age 13 , when he was sent to school in Philadelphia . He worked for the Pennsylvania Railroad and in anthracite coal mines . In 1857 , he moved to Pottsville , Pennsylvania , to become a civil engineer in the local mining industry . Civil War . With the outbreak of hostilities , Pleasants became a second lieutenant in the 6th Pennsylvania Volunteer Infantry , which enlisted for only three months . He re - enlisted as a captain in the 48th Pennsylvania Volunteer Infantry Regiment in July 1861 . The regiment initially saw service in the Western Theater , but came east and fought in such battles as Antietam , Second Bull Run , Fredericksburg and in the Wilderness . By 1864 , Pleasants had risen to lieutenant colonel and commanded the 48th Pennsylvania , which was one of the units outside Petersburg . Many of the 48th were coal miners , and Pleasants supposedly heard his men suggest running a shaft under the Confederate lines . Pleasants went to his superiors , who approved the plan . He battled a lack of supplies , as well as a lack of interest on the part of Union generals ( until other attacks on Petersburg failed ) . He was successful in his construction to such an extent that the explosion killed nearly three hundred Confederate soldiers . However , the Union troops under Ambrose Burnside failed to take advantage of the explosion and suffered considerable casualties in what is known as the Battle of the Crater . The Confederates recovered their original position . On August 1 , 1864 , Pleasants was rewarded for his ingenuity and efforts by being promoted to command the 2nd Brigade , 2nd Division , IX Corps by Brig . Gen . Robert B . Potter , the division commander . Pleasants was brevetted as a brigadier general on March 13 , 1865 . The citation brevetting him specifically mentions his service at Petersburg — it was not his fault that other officers bungled the opportunity . Pleasants returned to Pottsville after mustering out of the army in 1865 and resumed his role as a mining engineer for the Philadelphia and Reading Coal and Iron Company , rising to the positions of Chief Engineer and then Superintendent . Pleasants died at the age of 47 and was buried in the Charles Baber Cemetery in Pottsville . Fictional appearance ( " The Guns of the South " ) . In Harry Turtledove ' s alternate history novel , " The Guns of the South " , Pleasants was captured by Confederate forces late in the war . After the end of hostilities and his release from Andersonville , he decided to remain in the Confederacy , where his skilled labor would be more in demand . Later , Pleasants joins Confederate soldiers recalled to service to fight the turned - traitor " Rivington men " . When facing a seemingly impenetrable defensive position , he hears a fellow soldier jokingly suggest going under it and conceives a similar scheme as he did in real life . This scheme is quickly accepted by commanding general Nathan Bedford Forrest . Robert E . Lee , now Confederate President , orders that Pleasants ' name be kept secret , so Rivington men aware of Pleasants ' real history aren ' t tipped off . Here , infantry " are " able to capitalize on the opportunity .