The following data is extracted from Genealogy and Biography of Ontario County, New York.
John (3) Burtis, son of John (2) and Mary (Ater) Alburtis or Burtis, was born in 1749. He was appointed commissioner of the district of Cow Neck, October 4, 1775. The brief record of his service in the patriot army was : "He was stationed part of the time on the shores of Cow and Great Neck and part of the time at the New York Ferry," his duty being to cover the retreat of the army that crossed in the merciful fog of the night of August 29, 1776, in the very face of the enemy. He married, in 1773, Sarah, daughter of Thomas Foster, of Hempstead, Long Island, a determined Whig. Thomas Foster's sons. Nathaniel and Solomon, resisted the attempt of an English officer and his men to carry off their cousin; a soldier was killed in the melee and the two rosters were tried for murder. condemned, but finally ransomed by payment of a large sum of money. This happened while the British had possession of Long Island, and while the regiment to which this officer belonged was quartered at Foster's Meadow on the Burtis farm and occupying the old Alburtis house.
Source: Genealogy and Biography of Ontario County, New York