document.write("<table><tr><td><p>Jean Errard de Bar-le-Duc (1554-1610) was an early French fortification theorist, who proposed that the angle between the face of a bastion and its flank, and the angle between the two faces of a bastion should always be 90°. Errard is known as the father of the French school of fortification, although he did little practical engineering.</p></td></tr></table>");