About: http://webisa.webdatacommons.org/439901628

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	This is due to the fact that any device can hurl a projectile (spring catapult, torsion device, and of course trebuchet) but what sets the trebuchet apart from the rest is that it is powered by falling mass.
http://www.w3.org/ns/prov#wasQuotedFrom	explainxkcd.com