GRAVESEND, April 1st, 1851.
EDITOR EAGLE :--The local election has just terminated in the election of the following officers, viz:--
Supervisor--Barnardus Ryder, (Whig.)
Town Clerk--Nicholas Stillwell, (Dem.)
Assessor--Stephen N. Stillwell, (Whig.)…
Commissioners for leasing "Coney Island" Common Lands--Barnardus J. Ryder, Stephen N. Stillwell, Jaques J. Stillwell, Jacobus Lake, Jr., Nicholas Johnson, (Whigs)...
--Brooklyn Daily Eagle, Wednesday, April 2, 1851
You can read a tiny bit about leasing Coney's "common lands" in Charles Denson's Coney Island: Lost and Found.
I assume these Stillwells were part of the Stillwell family from whence Stillwell Avenue gets its name.