inclosed in a regular hexagon, this polygon having the advantage of offering more angles than the quadrilateral one. Every side of your hexagon, of which you will determine the length in proportion to the dimensions taken upon the place, will be divided into two parts, and upon the middle point you will elevate a perpendicular towards the center of the polygon, which will equal in length the sixth part of the side. By the extremities of each side of the polygon, you will trace two diagonals, which will cut the perpendicular. These will form the precise lines of your defense.”

“The devil!” said D’Artagnan, stopping at this point of the demonstration; “why, this is a complete system, Porthos.”

“Entirely,” said Porthos. “Continue.”