The Century Dictionary and Encyclopedia, 1911, p. 6457 available via googlebooks.
Above: Plat of T. 19 S. - R. 16 E. South Eastern District, La. East of the Mississippi. Surveyor General's Office, Donaldsonville, La. October 24th, 1854. Photostat of old plat. Bohemia Spillway Files, Guy Seghers Collection, Southeastern Architectural Archive, Special Collections Division, Tulane University Libraries.
To find other historic Louisiana plats, see the Louisiana Division of Administration's Historical Records page, and select under "Document Type" "Plats, Old." Then enter appropriate Land District, Township and/or Range.
To ascertain Township and Range coordinates related to the Public Land Survey System [PLSS], consult the Land Survey Information System online.