Conversely, the rain that falls from an old storm has more light oxygen in it-and that is the sort of rain that tends to fall on land.

Born of director Giuseppe Tornatore's childhood memories, this is a magic lantern in a Sicilian boy's hand, its warm light shed on the riches of life in a poor, stone-built land.

Wireless sensors are also cropping up on farms, to measure temperature, moisture and light on tracts of land where wired sensors cannot easily go.