1911 Encyclopædia Britannica, Volume 11… (1911)
“ Caxton speaks both of “a gallows,” and, in the older form, of “a pair of gallows,” this referring probably to the two upright posts. From the 16th century onwards “gallows” has been consistently treated as a singular form, a new plural, “gallowses,” having come into use. “The latter, though not strictly obsolete, is now seldom used; the formation is felt to be somewhat uncouth, so that the use of the word in the plural in commonly evaded” (New Eng. Dict. s.v. “Gallows”) . ”
