Chapel of St. Mary and St. Nicholas in the Torella of the City wall, by the Tower of London, H. III. (Anc. Deeds, A. 1653).
Torella, turella = small tower.
Another turella or turret on London Wall near Bishopsgate.
Granted to Sir John de Elyngeham by John de Gisors, 1314 (Cal. L. Bk. E. p.39).
These small towers were placed at frequent intervals along the Wall for defensive purposes.