An atlatl is a weapon predating the bow and arrow, used by American Indians in this area. On Saturday, Tamastslikt Cultural Institute had an Archeology Celebration, giving visitors like Tracker and his family a chance to try using tools their ancestors used.
As archeologist/anthropologist Tom Bailor explained it to me, an atlatl works like those plastic extenders people use to throw tennis balls for dogs. But this throws spears. These three photos give a good impression of how it works — a key being the second photo with the point of release shown.