When ancient Britons drew male genitalia on chalk hillsides, little did they know people would ape their customs millennia later

When I was at school there was a craze for scrawling penis graffiti on the chairs. Hapless teachers would look around the class to work out what all the sniggering was about, only to find a cartoon cock and balls between their legs. Now this classroom humour seems to have spread to outer space.

Teenager Rory McInnes painted a giant phallus on the roof of his parents' West Berkshire mansion, apparently after watching a programme about Google Earth.



The BBC delicately describes it as a "comedy painting", saying it was there for a whole year before his parents found out.

It is not the first time the stunt has been tried. In 2006 the Sun reported that "pranksters drew a willy on the roof of a top school" in Teesside that went ­unnoticed until it appeared on Google Earth.

Similarly for the benefit of Google Earth, pupils drew a 6m penis in weedkiller on school playing fields in Southampton in 2007.

Then there's the Cerne Abbas giant … but that's another story.