Talk About Suspense

Six hundred pounds!" announces Roger Howes, Thayer School machine-shop supervisor. He is adding weight to a rolling contraption that passes like a track over a student-built model bridge. "Six fifty!!" The heavy roller again passes safely over the bridge, and cheers erupt in the crowded classroom. "Eight hundred!" More cheers. "Nine hundred!" Hoots of glee. But this time the load is too much.

The bridge does not collapse, but loud cracking sounds are heard. It has reached what engineers call the failure point. But it is the strongest entry.

The bridge is one of 13 built by student teams in the Engineering 51 Bridge Design Contest, the culmination of a term-long design project. Each team is given the same amount and type of wood, glue, and plastic. Unlike the real thing, these bridges are supposed to break, and students hope that theirs will break when they are expected to. "Highest load" is only one of the categories they can win in. The primary goal is to produce a bridge that performs exactly as it is designed to perform.

"The point is accuracy of prediction," explains Howes, "not max load. If you predict 600 and it actually holds 900, you're off by a factor of one and a half, see. The guys who predicted 500 and it actually broke at 500 they did the job right."

Students also get points for displacement performance (how much the surface bends under the weight) actual displacement and accuracy of prediction. They do not win points for aesthetics, though each bridge is given an aesthetic rating, based on audience applause, before the testing. In this category highest honors go to a bridge that is blue with clouds and fishes painted on it.

Those who missed out on the event in December will have a chance to watch the bridges in action again next month; the contest used to be annual, but the course has become so popular that it is now offered twice a year.

• 60,000 watts electricity• 30,000 gallons water to create askating pond on the golf course• 21,000 feet electrical wire• 12,500 feet garden hose• 8,000 square feet of lumber orenough to build a six-room house.• 1,200 women guests •500 lightbuite Winter Carnival • 200 feet chiken wire CHECKLIST [CIRCA 1940)• 84 contestents from nine colleges•70 guards and ushers employed to COMPILED BYhandle the crowds JOE LOGAN '42 IN 1940• 50 men to groom the ski trails•48 number bibs• 20 students working 500 hours tobuild the snow sculpture•6 telephones• 42,000-watt floodlights• 4700-ampere spotlights•2kegs nails•2 bottles bluing•2 balls yam• 137 1/2 kilowatt transformer• 1 imitation horse head