Northumbria University student Kenneth Burns with his catapult

Attackers were reputed to have hurled severed heads of their enemies over the castle walls. That may or may not be true. But this year's miniature machines have a peaceful purpose. They'll be used to hurl eggs various distances, to be caught, preferably unbroken, at an English village fair.

The home-made trebuchets will be a highlight of the third annual World Egg-Throwing Contest in Swaton, Lincolnshire, on June 29. Eggs will "fly through the air with the greatest of ease", and helmeted competitors will try to catch them at the end of their flight.

Three points will be awarded for a successful "hurl" when the egg is caught without touching the ground and is unbroken. If the "target" is struck and the egg broken, the unfortunate would-be catcher wins just one point.

Andy Dunlop, President of the World Egg Throwing Federation, is organizing the contest in aid of local charities. Full details are shown on the official Web site.

Organizers hope that Sweet Briar Women's College in Virginia, U.S. will enter a novel trebuchet built by its engineering students. In a college contest on April 30, the projectile, a plastic lime, was held in a sling made from a purple bra C-cup.

A report by Jennifer McManamay in the Sweet Briar magazine says:

Engineering students used trebuchets to hurl plastic limes at a not-to-scale replica of the Alamo. Billed as a re-enactment of the Battle of La Margarita, the teams were scored on distance and accuracy...

"Only at a women's college can ... a trebuchet sling be a brassiere cup," Sweet Briar assistant professor of engineering Scott Pierce observed, watching his students maneuver their medieval-era weapons into launch positions.

A C-cup, purple in color.

The two trebuchets made of two-by-fours represent the students' end-of-semester projects. They had designed, analyzed, modeled, constructed and analyzed some more; it was time to see which machine would perform closest to their mathematical predictions. This is the point in the engineering process where reality and math intersect, Pierce said.

Team Jose Cuervo won the day, beating Team Los Positivo Fringe by a hairsbreadth. The prize was a candy-filled pinata that came with the option to load it into the winning trebuchet and chuck it.

"We're throwing this thing," said Amanda Baker, a junior engineering major. Sophomore Jenna Wasylenko wasn't so sure. "I don't think it will fit in my bra."

At least 12 trebuchets have been constructed or are being built.

A Latvian led team is currently putting its final touches to a machine constructed out of aluminum in Peterborough.

A US team from Houston are completing their final planning. The American team has a real problem flying the machine over, as "weapons of mass destruction" are not allowed on normal passenger planes. They intend to construct from scratch once they arrive.

The Welsh team from Cardiff is preparing, for the first time since 1294, to invade England with its homemade trebuchet. This fearsome team consists of the current World Record Holder for Dry Foam Flinging and Runner up in the World Pea Shooting Championship.

One English team is arriving from Northumbria University, to help beat off the Welsh challenge, with machines designed and constructed as part of a degree course.