Curfew. The custom of covering up all fires and extinguishing all lights in the city at sunset, and in the winter at 8 or 9 o’clock, at the ringing of the curfew bell, “couvre feu,” was introduced by William I.; and from the towers of St. Mary Redcliff and St. Nicholas churches it has continued to boom out its warning every night down to the present time. It is a curious survival of the Norman age.
Source: Arrowsmith’s Dictionary of Bristol. Edited by Henry J. Spear and J. W. Arrowsmith. Bristol 1884.