Hysterectomy

摘要

Tyres are remarkable pieces of engi-neering. At high speed in slippery bends they provide only a few square centimetres of contact with the road, yet they help a driver steer safely around the corner. Once, they were made entirely of natural rubber. These days they also contain rubber-like polymers, layers of steel braiding and textile reinforcements, all of which improve performance and cut fuel consumption. Now Pirelli, an Italian tyre-maker, is manufacturing fuel-saving tyres that are greener still by extracting one of their ingredients from rice husks.