Amazon.com description: Product Description: This book is a compilation of step-by-step instructions for how to build nine different types of catapults and trebuchets, including plans for: A PVC Pipe Trebuchet, A Tabletop Trebuchet, The World Famous Floating Arm Trebuchet, The Historical WarWolf Trebuchet, A Rat-Trap Catapult, The Mangonel (or Onager), The Greek Ballista, a Petraria Arcatinus And the Scorpion II. Each set of instructions include dimensional drawings of all wooden parts, lists of required hardware and sources, an abundance of photos, diagrams and detailed descriptions of the assembly process. Additional sections include historical notes for the different types of machines, warnings and safety suggestions, tuning tips, notes on scaling, tools and techniques and additional notes on even more kinds of catapults.