Ballista and Bolts

This is a model of the Greek -- Roman portable Ballista.  This was an element of artillery
 in the ancient and classical armies.  The two wing-like extensions are the ends of the
 bow and the bow string is drawn back along the tal end of the machine.  The tension is
provided by skiens of horse hair and silk loops twisted  which perform the project of the
heavy dart.  This model can shoot a dart in a shallow ark for a distince of approximently
 35 feet.