An unknown "Negro man" was enslaved by Eleazer Clark and included in his estate inventory.
In the probate abstract and on the first page of the estate inventory for Eleazer Clark, it states: "Inventory of the estate of Eleazer Clark, late of Well ... includes ... a Negro man, at £40."
Eleazer's wife, Elizabeth (Thompson) Clark (1705-54), apparently died in the same year. The source of these dates is: https://ancestors.familysearch.org/en/L71G-9DF/eleazar-clark-1699-1754. According to this source, they both died in 1754. It is unclear who died first or whether they possibly died together. Their son, Elezear, Jr., would presumably have been their heir and subsequent enslaver of this man.
Bibliography:
Maine Probate Abstracts Vol I 1687-1775 - John Eldridge Frost (1991)
York County Registry of Probate