English: Only a few of the original Ferguson rifles are extant. One of them is at Colonial National Historical Park, Yorktown, Virginia, where the above photographs were made. At the left is the profile of the piece with an 18-inch ruler to show scale. The picture at the right top displays look and breech mechanism, with screw breech closed. In the middle the screw breech is open, and at the bottom is seen the head of the same device in closed position.