He was commanding the Frankford Arsenal when he resigned from the United States Army on March 21 , 1861 ( effective April 3 ) .
Gorgas went on to serve at the Mount Vernon Arsenal north of Mobile , Alabama beginning in 1853 .
Gorgas was commanding the Frankford Arsenal when Gorgas resigned from the United States Army on March 21 , 1861 ( effective April 3 ) .
Gorgas went on to serve at the Mount Vernon Arsenal north of Mobile , Alabama beginning in 1853 .