Thomas was born in 1749 and passed away in 1818.
1790 Census.  * 2 white males over 16; 3 under 16; 4 women in all; 1 other free person; 0 slaves.
He was called "The Captain." He served in the Revolutionary War in Washburn's Guards of Maine for one month.  Mclellan, Thomas. Private, Capt. Isaac Washburn's Co. of guards; enlisted March 11, 1781; discharged April 11, 1781; service, 1 mo.; company stationed at Thomaston, Lincoln Co., [Maine].
After marrying Hannah Dyer he moved (between 1778 and 1782) to South Thomaston, Maine. It was after this that they began to build a family.
From S36 (p. 1, quoting from Eaton) "he was a shoemaker, farmer, and master of a coaster, by turns, as business and profit offered inducement. He was remarkeable for his strong love of money and economical, not to say penurious habits, which in later years amound to little less than monomania. He is said to have compelled his boys to stop the cow-bell every night with a wisp of hay to prevent the tongue from wearing."
He and his younger brother Simon "were the ancestors of all the early McLellans in the St. George River area" (S36).
More people appear on the 1790 census than can be accounted for by known family.
His gravestone is indecipherable; yet "it is reported by the 'Index to Revolutionary Veterans Buried in Maine' as 1818" (S36, 2). 
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