Obviously, I informed the British and French Governments of what I wanted to do,” says Tim Fitzhigham. “The French were very helpful initially, but then they inserted a new clause into their Shipping Act to make it illegal to row bathtubs within a mile and a half of the French coast. Which was a bit of a blow.”

Tim Fitzhigham is your proper, old-fashioned, British eccentric. Would anybody, of any other nation, ever seek to cross the seas in a bathtub?

Would they give it months of planning, and expense, and finish by rowing up the Thames with an actual broken shoulder caused by a mid-trip game of cricket? “If you pursue something with the belief and manic enthusiasm of a five-year-old, nothing seems insurmountable,” declares Fitzhigham, staunchly. “Most people stopped being 5 when they were 6. I did not.”

Let us be fair. As you can see from the pictures, of course, the Fitzhigham's bathtub probably doesn't look much like the one you have in your bathroom. “More like the whole bathroom,” he agrees. This was the upshot of months of negotiation with the UK shipping authorities who, unlike the French, appeared tentatively to approve of the whole concept.

French shipping law and British shipping law are, apparently, crucially different. The French rule things out. The British, if they can be swayed, rule things in.

“We will pass this as a shipping vessel,” one UK civil servant told the budding intrepid seaman, “although there will have to be some alterations. We are prepared to look a little silly. But not downright stupid.” The authorities wanted a masthead. Fitzhigham offered them a showerhead.

They wanted a covered area to hold essential electrics. Fitzhigham suggested a bathroom cabinet. They demanded an area of outboard between the bath and the sea. “Aha!” declared Fitzhigham, before dubbing it a bathroom floor, and having it laid with chequered tiles. “It may upset some bathtub purists,” he concedes.

As a bathroom, however, it functions. The showerhead is not merely decorative but works, too, sucking up water from below. Rather nicer to use in the Thames estuary, apparently, than the open sea. There's a plug, over which for the bulk of the journey Fitzhigham kept his foot.

It was properly plumbed, with pipes down to the sea. At his first, failed attempt to cross the Channel, a storm blew up. “I learnt that they are designed to keep water in,” he admits. Frantically bailing a bathtub dry while surrounded by water was beyond surreal.

Fitzhigham seems to be the point at which travel writing and comedy meet. He is a member of the Royal Geographical Society but was also nominated for a Perrier way back in 1999. He has been steadily gigging since then. The bath crossing was a fundraising gambit for Comic Relief and, out of a panicked sense of responsibility towards his sponsors, Fitzhigham accepts that he may have grown somewhat obsessed.

Crossing the Channel eventually took only nine hours, but the subsequent journey from Folkestone up the Thames went a little Apocalypse Now. Bad weather meant that he was stranded in Margate for a fortnight, most of which he spent moored in the bath, muttering. “I kept thinking of all the great mariners,” he explains. “Nelson, Ellen MacArthur. They wouldn't have got out of the bath.” Eventually he did, for a game of cricket. That was when he broke his shoulder. Just a chipped bone, but enough to make him lie to his doctor and sneak back to his bath a week later for the last 120 miles.

If it wasn't all written down and documented, you might think it fantasy. In honour of Fitzhigham's achievement, Thomas Crapper (who made his bath) created a special lavatory which bears his name. Most Thomas Crapper toilets say “Made in Britain” in the bowl. The Fitzhigham says “Mad in Britain”. “Finally,” says Fitzhigham, “I have my family seat.”

In The Bath by Tim Fitzhigham is published by Preface

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