To shoot Point-Blank is to be understood, that when the Cylender of the Piece lyeth level with the Horizon, so that the Ruler of the Gunners Quadrant being put into the Mouth of the Piece, the Line and Plummet hangeth Perpendicular, then that Piece lyeth in its true Position, to shoot Point-Blank.

And to make a good shot at a Mark, within Point-blank reach of the Piece, The Piece lying in that Position, as is before shewn ; then set up your Dispart upon the Muzzle ; then if you put your Eye down to the highest part of the base Ring (as you took the Diameter of) and bring the top of the Dispart in a right-line, with the Object at a Distance, that ought to be of the same Heighth from the Horizon at your Breech of the Gun and the Dispart, then is your Sight or visual Line also parallel to the Horizon, and if there be nothing defective in the Piece or Carriage, you will make a good Shot.

But if you intend to elevate your Piece, discharge it of some of the Quoins at the Breech, and by your Quadrant applyed to the Muzzle, you may elevate the Piece to what Angle you please; as may be performed by the New Sea Gunners Rule, whose Use is shewn at the latter End of this Book.