It's dirty talk of a very different kind

THE link between a Roman emperor and the great-great grandfather of the man behind Changing Rooms isn't obvious. But Vespasian and Victorian civil engineer Sir Joseph Bazalgette were both up to their necks in sewage.

As he climbed the senatorial ladder, one of Vespasian's jobs was to clean up the streets of Rome. The role was not without hazards, especially as mad emperor Caligula was his boss. When he spotted mud on the road, he had his guards fill Vespasian's toga with filth and excrement from the streets.

How Sir Joseph saved London from drowning in a sea of filth was related by his great-great grandson, TV producer Peter Bazalgette, in The Great Stink. The story behind the system of sewers that still relieve the capital of its waste today made for fascinating, if mucky, viewing.

Victorian London was a stinky place, where people peed and pooed everywhere.

It's not that toilets hadn't been invented. The remains of the first stone-built one, dating from 4000 BC, has been found on Orkney. The Romans constructed communal toilets and a short wooden stick with a sponge on the end that the toilet-goer dipped in water, cleaned himself and then put the stick back for the next person. The origin of the phrase "getting hold of the wrong end of the stick" arises from this.

By 1858 the River Thames was an open sewer. Anyone drinking a glass of water was probably drinking his neighbour's raw sewage. The smell - or the great stink as it was known - around the Houses of Parliament made MPs concentrate on finding a solution.

Sir Joseph headed the biggest civil engineering project of the 19th Century. Great-great grandson Peter went underground to view the brickwork. "It may be a sewer but I think it's absolutely beautiful," he said.

The Victorian Bazalgette's work is largely forgotten, as is Emperor Vespasian. This mule breeder rose from country bumpkin, through the ranks of the military, to become The Man Who Saved Rome.

He almost didn't make it after nodding off during one of Emperor Nero's interminable concerts. Vespasian was dismissed from court, although he later made a comeback to become Emperor and revive the Roman Empire's flagging fortunes. Like Sir Joseph, he left a lasting legacy - he built the Coliseum in Rome.