The Unbelievable Truth

David Mitchell is joined by guests Alan Davies, Holly Walsh, Angela Barnes and Henning Wehn who are obliged to talk with deliberate inaccuracy on subjects as varied as horses, cleaning, airports and New Zealand.

The Truths

Henning Wehn - Cleaning

- Romans used urine to clean their teeth, with Portuguese urine considered the best as it was regarded as the strongest. It worked because urine contains ammonia, and urine was used to clean teeth until the 18th century. Found by Angela.

- The first vacuum cleaner was so large it was horse-drawn. Six people were needed to operate the cleaner. Found by Alan.

- The "shoover" is a type of vacuum cleaner you wear on your feet and vacuums as you walk. Invented in 2006 by Electrolux as the "Dust mate" but nicknamed the "shoover", the company said: "As you walk, the base of the shoes collect dust on the floor without requiring any effort." Found by Holly.

- In 1992, six members of a Christian youth group cleaned off what they thought was graffiti from the walls of a tourist attraction in southern France, only to be told that what they removed was 15,000 year old cave painting of a bison. Found by Angela.

- At Oxford University, a female cleaner was made to remove a scrawling on a staircase saying: "Happy International Women's Day". Found by Angela.

Angela Barnes - Airports

- It is cheaper to park a light aircraft at Birmingham and Manchester Airports than it is to park a car there. Found by Henning.

- At Gloucestershire Airport, bosses found the best way to get rid of birds was to have a pan blasting Tina Turner songs at them, driven up and down the runway. Found by Holly.

- Almost 50% of UK flights taken by men aged between 20-45 are for stag dos. Found by Henning.

- Gerbils can sniff out adrenaline to detect terrorists. They were once deployed at Tel Aviv Airport to identify terrorists and hijackers, but the scheme ended after it was observed that the gerbils mainly caught innocent victims with a fear of flying. Successfully smuggled.

- You can buy a Playmobil airport security play-set, complete with body scanner. Successfully smuggled.

Holly Walsh - New Zealand

- New Zealand's 90 Mile Beach is 55 miles long. According to legend, it got the name because European settlers knew their horses could travel at 30 miles per day, and it took three days to travel along the beach. However, travelling along sand takes longer. Found by Alan.

- New Zealand has more Scottish piping bands than Scotland per capita. Found by Angela.

- The national basketball team of New Zealand is nicknamed the Tall Blacks. Found by Alan.

- New Zealand has "coffin clubs" where people meet up to decorate their own coffins. The idea, which started in 2010, is to help the elderly celebrate their lives and to challenge people's fears about death. Successfully smuggled.

- The national badminton team of New Zealand tried to get themselves nicknamed the Black Cocks, but the International Badminton Federation deemed the name inappropriate. The team however was flooded with offers of sponsorship from condom companies. Successfully smuggled.

Alan Davies - Horses

- The record for the horse long jump is shorter than the record for the human long jump. Found by Holly.

- Horse-drawn fire engines employed "alarm dogs" which ran alongside the engines, barking at people to get out of the way. Found by Angela.

- During World War One, horses were painting brown to camouflage them. Found by Angela.

- A painful horse's hoof could be caused by twitter, which is a 19th century term for an abscess on a horse's hoof. Successfully smuggled.

- The 19th century word "jumentous", means, "smells like horse urine". Successfully smuggled.

Scores

- Alan Davies and Holly Walsh: 3 points
- Angela Barnes: 2 points
- Henning Wehn: 0 points