Wilson provides photos of the building process, detailed and updated plans, plus construction information on ballistas, onagers and trebuchets. You will aso find information on catapult web sites and how to be included in some of the catapult contests around the country. Also included is some interesting catapult history, its strength and weakness as a weapon, and what it was that led to its demise as a functional war machine. There's no question that warriors have found more efficient means of lobbing projectiles at enemies, real and imagined, but has it ever been as much fun?