| submarine mines. | | mines. | | | | 1840. | Captain | Experiment on the _John | England. | Successful. Details not known. | Warner. | O'Gaunt_. | | | | | | June 4, | Colonel S. | Experiment to explode a | New York. |Successful. The operator was at a 1842. | Colt. | submarine mine by | | great distance from the torpedo. | | electricity. | | | | | | July 4, | " | Experiment on the U.S. | Castle |Successful. The operator was on 1842. | | gunboat _Boxer_ with | Garden, | board U.S. man-of-war at some | | electric submarine mines.| New York. | distance from the place where | | | | the explosion occurred. | | | | Aug. 20, | Colonel S. | Similar experiment on a | Potomac |Successful, the operator being 1842. | Colt. | schooner. | River, | stationed at a distance of 5 | | | America. | miles from where the mine was | | | | placed. | | | | Oct. 18, | " | Similar experiment on the | New York. |Successful. The operator being on 1842. | | brig _Volta_, 300 tons. | | board the revenue cutter | | | | _Ewing_, at a considerable | | | | distance from the scene of the | | | | explosion. | | | | April 13,| " | Experiment to destroy a | Potomac |Successful. The vessel was, at 1843. | | vessel of 500 tons _under| River, | the time of the explosion, | | weigh_ by electric | America. | sailing at the rate of 5 knots | | submarine mines. | | per hour, and to prevent the | | | | possibility of any collusion | | | | between the operator and crew, | | | | they left the ship a few moments | | | | before the catastrophe. Operator | | | | 5 miles distant.