1/2 the way done with my research paper

Today is Tuesday & I'm half of the way done with my research paper. I've explained what are Gastraphetes, Catapults and Trebuchets. Now all i have to do is the difference between a Catapult and a Trebuchet.

Trebuchet Research Paper

...Free Floating Trebuchet...

My class is currently doing a project on the history and designs of trebuchets. We are going to build one of the following Trebuchets; Free Floating, Fixed Counter Weight, and the Hinged Counter Weight. As you can see in the picture Below are to examples of the fixed and hinged Trebuchets.(Sodabob.com).The picture to the right is an example of a Free Floating Trebuchet(tsakshaug-nonesense.blogspot.com).

...Fixed counter weight on left and Hinged counter weight on right...