QI. Image shows from L to R: Alan Davies, Sandi Toksvig. Copyright: TalkbackThames.


BBC Two and BBC One panel show about quite interesting facts. 249 episodes (pilot + 17 series), 2003 - 2020. Stars Sandi Toksvig, Stephen Fry and Alan Davies.

Series R currently being recorded.
Series J, Episode 4 is repeated on Dave today at 9:20pm.

QI. Image shows from L to R: Alan Davies, Bridget Christie, Sandi Toksvig, Joe Lycett, James Acaster.

Series Q, Episode 15 - Quantity And Quality

Further details


- If QI were thinking of starting a high-quality airline, but don't have the quantity of money required, there are various ways they can save money. The main way is to reduce the amount of fuel you use, which saves money and helps the environment. In 2013, Samoa Air became the first airline to charge passengers according to their own weight, paying one Samoan tala (29-30p) for every kilo that they and their luggage weighed. White planes are more efficient than dark planes, because dark paint contains more pigment and thus weighs more, weighing as much as eight passengers. You could also polish a plane with no paint, but you would need to wash it more often to offset corrosion, and white paint is cheaper because the money you saved on fuel would instead be spent on washing the unpainted plane. In 2018, United Airlines started using lighter paper for their in-flight magazine, saving 1oz per copy, £11 for a full flight, and over the course of a year saves 170,000 gallons of fuel worth $290,000. Their beverage cart also weighs half of what the old one weighed. Some flights have stopped duty-free sales. In the 1980s, head of American Airlines Robert Crandall removed a single olive from every salad served to their customers, which saved $40,000 a year. In 2009, Japan's All Nippon Airways asked passengers to visit the toilet before boarding, because a full 767 plane could hold 240lb of urine inside its passengers, and by going to the toilet they could reduce carbon emissions by 5 tonnes over the course of a month.

- You can make money from fresh air by selling jars of clean air online to places with high pollution levels. In 2015, Moses Lam from Edmonton, Canada, as a joke sold a bag of fresh Canadian air on eBay for CA$0.99. It sold, so Lam sold a second bag and bids got up to CA$168. Inspired by this, Lam quit his job as a mortgage broker and now sells Canadian Rockies air. A single eight-litre bottle costs US$24, and his company, Vitality, has sold over 200,000 units, often to countries with very low air quality. You can also buy Swiss mountain air for £17 a can, and also buy air from Yorkshire, Wiltshire and Wales. A company called Aethaer, founded by Leo De Watts, has coined the term "air farming" to describe this business, and farms air in Somerset.

- Tangent: The country with the best air quality in the world is Finland, followed by Iceland, Sweden, Estonia and Norway. The UK is 25th, behind Singapore and above Oman. Sweden have fallen down the air quality scale however because they have car tyre with spikes to stop cars from sliding on ice and snow, but the spikes dig up the tarmac, releasing pollutants. The place with the worst air quality is Kanpur in Uttar Pradesh, which is nicknamed "the Manchester of India". The worst place for pollution in London is the Underground. According to a study at University College London in 2001, the air quality in carriages is 73 times worse than at street level. If you take one single 20-minute journey on the Northern Line, it is as bad as having a cigarette. The pollution is due to iron oxide particles caused by wheels grinding on the rails when trains break.

- It might be a bad idea to remove all the dead wood from the Houses of Parliament because you could destroy nearly all of the building. Until 1826, the Palace of Westminster kept all its financial records on tally sticks, where a stick was split into two when you issued a debt, and the sticks were tied together again when the debt was paid. Paper records then superseded the sticks, so they decided to burn the sticks. On 16th October 1834, the Clerk of the Works, listed in various records as either Mr. Whibley or Mr. Woebley, order two cartloads of tally sticks to be burnt in the basement stoves of the Palace of Westminster. This fire ended up burning down both the House of Lords and House of Commons, but Westminster Hall was saved because the wind changed. Part of the problem was that the chimneys had not been properly maintained, due to chimney sweeps cutting footholds into it to make cleaning it easier, residue building up, and the copper linings of the chimneys catching fire. The fire spread to the entire wood interior of the building. At the time there was no fire brigade, just the insurance companies, and it took five hours for the fire boat to get to the site because the tide was wrong. It was the largest fire in London since the Great Fire of 1666. J.M.W. Turner painted several canvases of the disaster, while Constable sketched the fire while sitting in a hansom cab on Westminster Bridge. The Palace we see today was made after the fire by Charles Barry and Augustus Pugin.

- Tangent: The panel make reference to the fact that the Clerk of the Works sounds like he has the name Mr. Wibberley-Wobbly and must be very clumsy. Joe has a character called Christopher Butterslip, an auctioneer who drops everything whose catchphrase is: "Whoopsie plops!"

- Tangent: The fire affected the length and breadth of Trafalgar Square because the very objects which defined the imperial standards of measurement were also destroyed. Thus, we had no way of ultimately deciding the length of something. However, there is a bronze plaque in the wall of Trafalgar Square stating all of the measures. Mathematician and astronomer Sir George Airy, made a series of plaques to make sure this could never happen again, so the standards were triplicated. You can these plaques also in the Great Hall of the Guildhall and the gate of the Royal Observatory in Greenwich. To find the one in Trafalgar Square, face the National Portrait Gallery, you will see a cafe and a bench, and it is around there, hidden from the view of most people. Trafalgar Square was being built at the time, opening in 1844.

- The panel are asked which is Sandi's favourite Quality Street. The answer is the play by J.M. Barrie, from which the chocolate assortment gets its name. This four-act comedy was a big hit in London, opening in 1901 and playing for 495 performances, and the play is still performed. The play follows Phoebe, an unmarried woman in her early 30s, whose former love Captain Brown returns from the Napoleonic Wars. Phoebe is worried Brown won't love her anymore, so she disguises herself as a younger girl to impress him. This theme of staying young reappears in Barrie's most famous work, Peter Pan. The first actress to play Phoebe, Maud Adams, went on to be the first person to play Peter Pan on Broadway, playing him over 1,500 times, and becoming one of the first actors to earn over $1million a year. Adams was also an inventor, assisting in the development of colour photography, and she was probably a lesbian, being buried next to her secretary for over 40 years, Louise Boynton, although it might have been the case that Boynton booked a double plot. (Forfeit: Green triangle; Purple one; Toffee penny)

- Tangent: There are four streets in the UK called "Quality Street", one in Merstham, which was named this after the two original stars of the West End production of the play moved there. The other three are in Scotland. There appear to be no shops in any of these Quality Streets that sell Quality Street chocolates. The chocolates were invented by John and Violet Mackintosh, who created a new style of in 1936, and used the characters from the play in their packaging. In 2018, Which? Magazine did a survey and found that chocolate selections always have fewer of the chocolates that most people actually like. They asked about 1,000 people to name their favourite, and the two most popular ones were the purple one and the green triangle. By preferences, they should appear 11 times in the box, but they only appear five or six times. Heroes, Wispas, Twirls also have the same issue. James complains that chocolates picked as the favourites are boring, saying he prefers the toffee finger and caramel cup. Bridget says that these are the same, to which James corrects her and calls Bridget a racist.

- The letter the Romans used to write the number 1,000 was an "I" in brackets. M was not used to mean 1,000 until the Middle Ages. The Romans tended not to use many large numbers. Examples of the use of (I) can be found in a monument erected in the Roman Forum to commemorate a victory in the First Punic Wars, which featured "I" in many brackets, repeated at least 22 times, which represents the 2,200,000 bronze coins they looted from the Carthaginians. Later on the Romans wrote 1,000 using an "X" in a circle, and later the Greek letter Phi and then an "8" on its side which today is the symbol for infinity. Finally, in the Middle Ages "M" became used, probably from the Latin for 1,000, which is, "mille". (Forfeit: M)

- Tangent: Today (I) is used as an emoji for the buttocks.

- Tangent: In school today, we write the number "9" in Roman numbers as IX, but that rule also comes from the Middle Ages. The Romans has a mixture of contractions, sometimes writing XI but also writing VIIII. These variations still appear on clock faces. Sandi argues that clocks should have IIII for 4 and IX for 9, because for the first four are all "I"s, then the next four have all the "V"s and the last four have all the "X"s, because it looks better. Big Ben however has an IV for four.

- The biggest thing you could buy for a quid is Chelsea F.C. In 1982, Ken Bates bought the club for £1, and he sold in 2003 to Roman Abramovich for £140million. Today Chelsea is believed to be worth £1.5billion. Other companies that have been bought for a pound include British Home Stores, Barings Bank, Reader's Digest and Homebase. Elsewhere Rover was sold to BMW for £10. These small fees are called a "consideration", which is a legal necessity in a contract, as something has to be paid. This was previously known as "peppercorn rent", with Bath University still paying n actual peppercorn to the city as ground rent. (Forfeit: Blue whale)

- Tangent: The most recent version of the 12-sided pound coin has a number of features to deter forgers, including a hologram at the bottom of the Queen's head, which shows either a "1" or a "£" depending on how the light shines on it.

General Ignorance

- Skid marks are made from bitumen heating up. As the breaks stop the wheels from turning, the friction between the tyres and the surfaces results in hightemperatures that cause the tar to belt, along with the bitumen. The bitumen oils in the asphalt rise to the surface, and once the surface cool down the skid marks will fade away. The technical term for a skid mark is, "a bituminous material smear". (Forfeit: Poo; Tyres; Rubber)

- Tangent: Joe complains that the road sign for slippery road makes no sense, because the skid marks made by the car make no sense.

- Tangent: The word "skid" comes from the Old Norse word "ski", meaning a stick of wood, namely a piece wood that was laid down to help move logs. The Open University offers a course called "Analysing Skid Marks", which is used in motor crash forensics. The first citation in the OED for "skid marks" referring to stained underwear comes from Barry Humphries, in a Barry McKenzie cartoons, published by Private Eye in 1968.

- The panel are shown a picture of a forest and are asked how many trees are in it. In fact, there is only one tree. The picture is of the Trembling Giant, or Pando, which looks like lots of aspens, but is actually a single organism that is possibly a million years old. It is in Utah and is a male organism that produces asexually, creating new stems underneath from the roots. Each of the 47,000 stems are genetically identical. However, it hasn't been growing for the past 30-40 years, so it might be dying, as new "trees" die they are not being replaced. It is possibly the largest organism on Earth, by weight. The roots are believed to be at least 80,000 years old. (Forfeit: None)

- The Haydn Quartets were written by Mozart and dedicated to Haydn. Haydn was a kind of mentor to Mozart. Haydn didn't actually invent the quartet, but when he was about 18 he was asked by Baron Furnberg to come up with something that four amateurs could play at home, which is how string quartets began. (Forfeit: Haydn)

- The type of tool used to make jigsaw puzzles is either a laser or a rolling press today, and originally they were made using a fretsaw. Jigsaws were not invented until the 1850s, and the first jigsaw puzzle was invented in 1762. The term "jigsaw" came from a London engraver called John Spilsbury and were originally called "dissected puzzles". He created a map on wood and cut out the countries, so the first jigsaw was designed to teach children about the countries. (Forfeit: Jigsaw)

- Tangent: A jigsaw puzzle manufacturer typically uses the same cutting pattern for lots of different puzzles. Thus, if you buy two puzzles of the same size, from the same company, of two different pictures, you can mix and match and still make a puzzle. Art professor Mel Andringa creates puzzle montages using them.


- The Audience: -9 points (Sixth victory)
- James Acaster: -12 points
- Bridget Christie: -13 points
- Joe Lycett: -14 points
- Alan Davies: -42 points

Broadcast details

Friday 7th February 2020
30 minutes


  1. Saturday 4th April 2020 at 9:00pm on BBC2 (45 minute version)

Cast & crew

Regular cast
Sandi Toksvig Host / Presenter
Alan Davies Regular Panellist
Guest cast
James Acaster Guest
Joe Lycett Guest
Bridget Christie Guest
Writing team
James Harkin Script Editor
Anna Ptaszynski Script Editor
Sandi Toksvig Script Editor
Mike Turner Question Writer
Production team
John Lloyd (as John Lloyd CBE) Series Producer
Piers Fletcher Producer
Nick King Editor
Jonathan Paul Green Production Designer
Howard Goodall Composer



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