The other day I bought a lawn-mower. It was an emergency purchase as the gardeners that usually look after the communal garden where I live had not turned up for three weeks. As any of you who garden will know, three weeks is a long time in a garden during May and June, and a very long time for a lawn. We have our annual garden party coming up in a week so something had to be done, and soon. We quickly established that not one of us could get our old petrol mower to start. S