In 1738 he was a trooper under command of Captain Johannes Ten Broeck, Ulster county Militia. [Second Annual Report of State Historian of the state of New York, Colonial Series Vol i p 610.] He resided at Hurley, where he made his will, Septerber 15 1787. On this instument, which disposed of a good estate, teh findings of hte Supreme Court of New York, in 2 Gaines, 345, were: that Cornelius Newkirk died testate in February, 1788, having two sons, Philip and Cornelius and four daughters, Jannet, wife of Benjamin Roosa, Leah, wife of Garret C Newkirk, Hendricka wife of Cornelius Du Mond; Arientje, wife of Petrus Du Bois, and his grandson Petrus, the son of Ary Newkirk, a deceased son, who was an infant; and that in 1793 his son Philip Newkirk departed this life having as heirs his children Cornelius P, Elizabeth and Maria who died in infancy.

The children of Cornelius an dDIna (Hoogteeling) Newkirk, baptized at Kingston, Ulster County, New York.