The USGenWeb Census Project Intro to Federal Census Research 1840 Census Facts Series: M704 Rolls: 1 - 580.

Sixth U.S. decennial population census. U.S. population: 17.1 million (14.6 million free, 2.5 million slave) Census conducted by U.S. marshals under the direction of the Secretary of State. Census day: 1 June 1840. Mandated copies: Two sets, one sent to the federal district court, the other to the Secretary of State. Information Provided on 1840 Census: Name of family head age sex race slaves number of deaf and dumb number of blind number of insane and idiotic and whether in public or private charge number of persons in each family employed in each of six classes of industry and one of occupation literacy pensioners for Revolutionary or military service.

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