Mounted A Cannon On The Roof

From Mrs. John Graves Simcoe's Diary:

Mon. 29th Rode before breakfast. At Navy Hall, the " Onondaga " arrived from Kingston in 22 hours. There is a large stone house, built by the French, in the Fort at Niagara...." .

Source - Navy Hall, Niagara

"NOTE. This house is a large stone building which stands within the precincts of the American Fort, and was built by the French prior to 1750...[with] a timbered roof. During the War of 1812 the Americans are said to have torn it off, made a flat roof, with stone walls projecting a foot or so above it, and to have mounted a cannon on the roof."