Shopping carts are surprisingly expensive ... If you left the track, a rod passing through the wheel locked it. A third magnet would disarm the brake when you entered the store again.

Shopping carts are surprisingly expensive ... If you left the track, a rod passing through the wheel locked it. A third magnet would disarm the brake when you entered the store again.

He put wheels on the four feet and then a basket on the seat ... ANDREW WARNES: The book is how the shopping cart explains global consumerism. HOPKIN: Its author is American studies professor Andrew ...