During the Plantation Gates Condition Survey in 2016 undertaken by Wigan Building Preservation Trust and Wigan Council, a handcarved inscription was discovered on the top of the arch.
Eventually the inscription was deciphered to be Harold Hennefer.
Harold Hennefer - born in 1899.
In 1938, he was living at 40 Snowdon St, Bolton.
Occupation - Rock Tophall Layer (Heavy).
Sounds like a job that could find him on top of the Plantation Gate?