Martin McNary served in Captain Elias Stillwell's Company in the 1st Regiment, Connecticut "Line". The published roll shows him paid from June 1 to Dec 31 1781 (Record of service of Connecticut men..., p. 319-20). The service record card file (on Fold3) shows him enlisted June 1, 1781 and has a number of roll extracts showing in the 6th of the 1st. The service file says he deserted 1783, but his pension file has a 1783 affidavit showing that he had provided a replacement soldier at West Point. His statements in the pension file (also on Fold3; S42953 ) are generally consistent with the service record, though a few times he gave different details he did specify several times that he had been in Stillwell's Company.
This Martin McNary lived out his days at Fishkill, New York and died in adjacent Philipstown in 1825. He is commonly believed to have been the son of Martin McKenery, a Scots-Irish adventurer who served in the F&I War and lived at Middletown and later at Haddam, Conn. A 1785 letter by the elder Martin mentions that he had a son Martin, his oldest, age 25 and a blacksmith. Martin gave the ages of 9 other children in that letter and all of them can be verified from town and church records to have been accurate, most exactly correct and a couple of them within less than +1 year. This son Martin's implied birth in 1760 was 3 years before his father Martin's only marriage of record, which was in Middletown 1763 to the widow Mehitabel (Johnson) Blake. A letter written by a grand-daughter of the elder Martin in 1875 says that the son Martin grew up in Colchester (some 20 miles to the east) among his mother's people (Bettis family).
I do find records at Colchester for the Bettis family and for an (illegitimate) child that may have the younger Martin. But there's no real evidence linking the Fishkill Martin and Colchester, or the Bettis family, or the older Martin. And there are conflicts that raise doubts: there are very persuasive age-at-date records for both, and the calculated birth year for Martin "of Fishkill" is 4 years earlier than that of Martin "son of Martin". And Martin "of Fishkill" was a farmer and there is no evidence that he or any his sons ever was a blacksmith. And the elder Martin is known to have had several relatives from abroad visit him at Middletown, suggesting a real possibility that the Martin who wound up in Fishkill was a close relative (e.g. a nephew) but still someone other than his acknowledged son.
So I find so far that the common belief that Martin of Fishkill was the son of Martin of Middletown to be unproven and doubtful.
Is there any record that can show where exactly Martin McNary was (what town) when he enlisted at the beginning of June 1781? Absent a record specific to him, is there any record showing orders that may have sent Stillwell to specific places in Connecticut to recruit, or giving the actual location of Captain Elias Stillwell on any dates around June 1 1781?
More About Stillwell's Company
I understand from the published sources that the Connecticut Line, mostly deployed in the Hudson Valley of New York, was being reorganized around the time that Martin signed up. The old 3rd and 4th Regiments were consolidated into the new 1st. In earlier years many of the rolls listed the soldiers' home towns but that does not seem to be the case in the 1781 reorg. I found 11 of the 48 men listed in the roll of Stillwell's Company (as published, evidently from end-of-1781 payroll) listed in Captain Allin's Company under Colonel Wyllys in the old 3rd Regiment of 1779. It seems a number of survivors from Allin's Company were transferred to Stillwell's command. Six of those 11 men were from Colchester.
I have the impression that company-level officers were sent "home" from the Hudson Valley to Connecticut during the reorganization to enlist more men to fill out the roster. That's why I'm imagining that maybe the Martin who did enlist on or about 1 June 1781 may have been standing in some particular town in Connecticut at that moment.
What it Would Mean
If the Martin who enlisted in Stillwell's was at/of Colchester, it would be the key to building the first chain of evidence connecting the Martin who was at Fishkill to anything specific about the family history of the elder Martin... it would be very significant.
If he was at Middletown, it would weigh less... it would tend to show there was some connection but not say much about the question of "son or nephew".