Drawbridge

The rooms inside the fort hold many interesting objects and stories.

National Park Service

From original plans and writings that survive, we know that the fort was equipped with a drawbridge, although no detailed descriptions of how the bridge operated were found. The mechanism you see before you is a common design of the time and works on a counterweight system. The weights on each side were started by manpower and would then roll down the track to bring the bridge up. Interestingly, the drawbridge was not raised during the siege, most likely because the British concentrated their attack on the north side of the fort. 

From the Orderly Book of the1st NY Regiment:
Fort Schuyler 2d October 1779
Garision Orders

...the Draw Bridge + main gate to be Opened at Eight OClock, the whole to be shut again at the usual time as beforeBy Order of Colo V Dyck