Lucas, Fielding Jr is an eminent cartographer, publisher and artist. He is one of the successful map makers of Baltimore. His atlases were first published between 1815 and 1817. In his atlases, the maps were related to the 1822 edition of Philadelphia atlas, which was produced by Carey and Lea. Lucas, Fielding Jr is accredited to publish the first color plate book, which was known as 'Flora's Dictionary'. 'Lucas General Atlas' is considered to be the finest general atlas produced in the United States.
Lucas, Fielding Jr founded the Lucas Brothers Incorporation in early 1800s. He also served as the manager of Conral, Lucas and Company, a publishing firm in Philadelphia. Lucas, Fielding Jr published an annual calendar, namely 'The Metropolitan Catholic Calendar and Laity's Directory' in 1834. In 1838, the calendar was renamed by him as 'Metropolitan Catholic Almanac'. Lucas, Fielding Jr inserted the map of United States in the 1845 issue of the calendar.