 He and his associates formed the Compania de Vapores de Nicaragua, but the company eventually was absorbed by Cornelius Vanderbilt's American Atlantic and Pacific Ship Canal Company.Brown returned to the practice of medicine from 1852-1877.He was the medical advisor along with the architect Calvert Vaux, for plans to build the Sheppard Asylum, a modern hospital for mental patients, in Baltimore, Maryland, which opened in 1891.