A spring on the steps Sometimes the simplest of things amuse children and adults alike. This is just a coil of wire - but it's an original Slinky, not one of those silly multicoloured plastic ones, (which serve quite well as hippie bracelets, I seem to recall)- it's just nice, shiny, slinky metal. It's a metal spring, it walks downstairs, it's a Slinky.The Slinky was invented by accident by Richard James. Whilst working on a spring designed to keep instruments steady at sea, he knocked one off a shelf and watched it "walk". "This thing has a life of its own!" he declared and the first Slinky was born and marketed in 1945.I remember seeing one being demonstrated when I was a kid. The guy said you had to "wind it up" - by letting its coils flow from one hand to the other - before releasing it at the top of the stairs. For years, I thought you had to do that. But you don't. All you need is gravity. And levity. Yes, Spring is here.