Thomas Edgeworth Courtenay Thomas Edgeworth Courtenay ( April 19 , 1822 – September 3 , 1875 ) was a member of the Confederate Secret Service and the inventor of the coal torpedo , a bomb disguised as a lump of coal that was used to attack Union steam - powered warships and transports . Birth and early life . Thomas Edgeworth Courtenay was born in Belfast , Northern Ireland , the youngest of 6 children . He was distantly related to the Courtenay family who held the title Earls of Devon and were seated at Powderham Castle in Exeter , and was a distant cousin to the novelist Maria Edgeworth , but his own family was not well - to - do . His oldest brother inherited the family property and his other siblings had all come to America to seek a better life . Courtenay came to the United States in 1842 , first staying with his brother William in Vicksburg , Mississippi , before settling down in St . Louis , Missouri . He and his brother were brokers , shipping supplies down the Mississippi River to plantation owners , and buying their cotton for shipment to England . Thomas also established himself as an insurance agent , selling fire , marine , and life insurance from an office at the corner of Main and Olive streets in St . Louis . In January , 1860 , Courtenay was appointed sheriff of St . Louis county to fill out the term of Sheriff Cere , who had died in office . The office dealt mainly with civil matters such as foreclosures and sheriff ' s sales . Courtenay did not run for election to a full term as sheriff and was out of office by the end of August . When he left office , there was a significant shortfall in the books of the sheriff ' s office . Courtenay blamed the problem on his chief deputy , but the matter was Courtenay ' s responsibility , and the unresolved debt put a damper on his business efforts . When the Civil War broke out , he moved his family to relatives in Harford County , Maryland and established a new insurance office in Baltimore . The Civil War . In 1863 Courtenay returned to St . Louis to pursue a lawsuit against his former deputy for recovery of the funds missing from the sheriff ' s office . It became clear that the suit was hopeless and that he would be held financially responsible . Moreover , the Union authorities were suspicious that Courtenay was a rebel sympathizer , due to his business dealings in the South . In fact , Courtenay " was " a Confederate sympathizer , and had written to Confederate Secretary of War Leroy Pope Walker in May , 1861 , offering to act as a purchasing agent for Confederate supplies in the Trans - Mississippi Department . With no prospect of recovering his business in St . Louis and his family well cared for in Maryland , Courtenay turned to the Confederacy . He obtained a volunteer appointment to General Sterling Price ' s staff , although exactly what he was doing is unknown . In August 1863 , Courtenay approached Price with a plan to attack Union shipping by means of an explosive device disguised as a lump of coal , the coal torpedo . The coal bombs would be planted in the coal piles used to fuel Union steamships and locomotives by a team of operatives working behind enemy lines . When a coal bomb was shovelled into the firebox , it would explode , resulting the explosion of the pressurized steam boiler and the destruction of the vessel . Courtenay was sent to Richmond , Virginia carrying military dispatches , and he remained in Richmond to implement his plan . He first wrote Jefferson Davis on November 30 , 1863 , explaining his scheme . Davis approved and forwarded Courtenay ' s letter to Secretary of War James A . Seddon , who arranged for the castings to be made by the army artillery shop in January , 1864 . Courtenay was motivated by a Confederate Bounty Law that offered a reward of up to 50 % of the value of Union shipping destroyed by means of new inventions . However , the Confederacy had not established a legal framework that would allow private citizens to conduct attacks that were essentially military in nature . A secret bill authorizing the formation of independent secret service corps was passed by the Confederate Congress on February 15 , 1864 . Courtenay was given a captain ' s commission in the Confederate Army and permission to form a Secret Service Corps of up to 25 men . The Corps was authorized to attack any Union military vessel or transport carrying military goods found in Confederate waters , but was forbidden to attack civilian shipping or Union shipping in Northern waters . Courtenay would not draw a regular Army salary , but would receive up to 50 % of the value of ships and cargo destroyed or captured , payable in Confederate war bonds . Courtenay planned to purchase a coal barge and seed it with coal torpedoes , as a means of getting his bombs into the ships of the Union blockading fleet , but the plan either failed , or was never carried out . Unfortunately for Courtenay , Confederate correspondence giving details of the plan was captured and Courtenay and his associates became wanted men . Union Admiral of the Mississippi David D . Porter ordered , " I have given orders to commanders of vessels not to be very particular about the treatment of any of these deperadoes if caught — only summary punishment will be effective . " Captain Courtenay obtained permission from President Davis to leave the country and go to England to raise money for the Confederacy . Courtenay kept in contact with his corps , and directed their actions from abroad . The coal torpedo was credited with sinking the " Greyhound " , a private steamboat that had been commandeered by General Butler for use as a floating headquarters on the James River , on November 27 , 1864 . Courtenay also took credit for the destruction of the gunboat USS " Chenango " as she sailed from New York Navy Yard on April 15 , 1864 . After the war . While in England , Courtenay attempted to sell his coal torpedo to a number of foreign governments , including England , France , Spain , and Turkey , all without success . He returned to the United States in 1868 , but he was in poor health for the rest of his life , and died at the age of 53 at Jordan ' s Sulphur Springs near Winchester , Virginia , on September 3 , 1875 . He is buried in Mt . Olivet Cemetery in Baltimore , Maryland . Marriage and children . Thomas Edgeworth Courtenay married Mildred Ann Clendenin on August 25 , 1847 in Louisville , Kentucky . Mildred ' s father , James Clendenin , was a merchant in Louisville , who had met Courtenay on a trip to St . Louis . Mildred ' s mother was from the Peay family of Virginia . Mildred ' s Uncle Austin Peay had married Peachy Speed , sister of Joshua Fry Speed and James Speed . Since Mildred ' s father had sold his home and was in the middle of moving to St . Louis , Thomas and Mildred were married at Farmington , the Speed family plantation in Louisville , Kentucky . Thomas and Mildred had five children : Mildred , Austin and Ellen went to England with Thomas in 1864 and returned in 1867 . When Mary was born in 1867 , Mildred was living with relatives in Maryland , while Thomas remained in England trying to sell his invention .