The gallery, accessed by a stairway, the small window for which remains, was removed in 1878.
A gallery in the church was removed during Victorian restoration in 1866.
The museum's galleries on the 52nd floor have since been removed, however.
Stained glass was added to windows and the gallery was removed.
The gallery, staircase and door were removed during the 1865 improvements.
The reconstruction, which cost £5,769, reduced the capacity of the church by approximately 30% to around 900 because the galleries were removed.
The galleries were removed, reducing the seating by more than half.
The musicians' gallery at the north end of the hall was removed.
By 1924 the gallery had been removed and the old organ replaced by a new one.
During the recent extensive restoration a gallery and shelving from the 1950s/60s were removed.