Farm Line Maps of the City of Brooklyn compiled and drawn by Henry Fulton, Civil Engineer of Brooklyn, Long Island from oficicial records and surveys. Published by J.B. Beers and Co. in 1874.
This map includes the planned-but-never-built Brooklyn Basin. It is possible that Fulton, who was probably more focused on the historic farm lines, believed that the Basin was destined to be built soon but now it's existence on his map, as well as several others, is a caution that verification is important.