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


  • TV panel show
  • BBC Two / BBC One / BBC Four
  • 2003 - 2021
  • 283 episodes (19 series)

Panel game that contains lots of difficult questions and a large amount of quite interesting facts. Stars Sandi Toksvig, Stephen Fry and Alan Davies.

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Series Q, Episode 15 - Quantity And Quality

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

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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.

- XL Tangent: The Elves have been all over the world collecting fresh air for the panel. Joe has some Slovenian air collected by James Harkin. James has some Tasmanian air collected by Anna Ptaszynski. Sandi has air from the Scottish Highlands collected by Anne Miller. Bridget has air from the Canary Islands collected by Mike Turner. Alan has air, collected by Alex Bell, from The Hudson Bay - a pub in West Ham.

- XL Tangent: Bridget claims to be very good at smelling. When she was pregnant her husband Stewart Lee was out, and when he came back she said: "Have you been eating Nice 'n' Spicy flavoured Nik Naks?" He said: "No, but there was a bag in the room that I was in."

- 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 tyres 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.

- XL Tangent: The Henry Ford Museum in Michigan contains what is claimed to be Thomas Edison's last breath in a test tube. The label accompanying it reads: "Thomas Edison was Henry Ford's hero, as well as his friend. During Edison's final illness this test tube was close to his bedside. Upon his death, it was sealed with paraffin wax. Edison's son Charles later sent his father's last breath to Henry Ford, knowing their close relationship."

- 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, ordered 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 wooden 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 and 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.

- XL: The heaviest reading material in the universe Googolplex Written Out by Wolfgang H. Nitsche. Googolplex is one of the largest numbers known and theoretically it is available to buy in print, but there is not actually enough material in the universe to write the number out. A googol is one followed by 100 zeros. A googolplex is a googol followed by a googol of zeros - 10 to the power of 10 to the power of 100. There are fewer particles in the universe than the number of zeros in a googolplex, thus it is impossible to write it out. Googolplex Written Out is a proper book with an ISBN, but there is no ISBN for individual volumes of the book because there not enough ISBNs. The book itself is just full of zeros, with a single 1 at the start. Googolplex was named by Edward Kasner, and if you started counting to the number at a speed of two digits per second, the universe would end before you could finish. In comparison, counting to a billion would take you 15 years, 308 days, nine hours, 41 minutes and 50 seconds.

- XL Tangent: Sandi has the first volume of the book, but Bridget cannot look of it because of her trypophobia - her fear of clusters of small holes and bumps. This is a phobia she mentioned on her last appearance on the show. Sandi asks if Bridget could play Twister, and Bridget says she can because the circles are far apart. Her phobia is triggered by the holes being close together and being the same size, so as Sandi suggests Bridget could eat a crumpet.

- XL Tangent: According to the Guinness Book of Records, the smallest book in the world is "Teeny Ted from Turnip Town" by brothers Robert and Malcolm Douglas Chaplain. It is a 30-page book carved on a pure crystalline silicon page. It measures 70 micrometres by 100 micrometres, and was etched using an ion beam at a university in Canada. The book can fit into the width of a single human hair, and you need a scanning electron microscope to read it. While a large print copy is available, the small one is about £10,000.

- 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)

- XL Tangent: Wendy Darling is related to Long John Silver. Wendy is based a real girl named Margaret Henley, who was unable to say the word, "friend", so she used to refer to J.M. Barrie as her, "wendy", as in "friendy". Margaret's father was William Ernest Henley, who is best known for writing the poem "Invictus". William lost his leg to TB when he was aged 12, and he was friends with Robert Louis Stevenson, author of "Treasure Island", who used William as the basis of his one-legged pirate Long John Silver. Thus the person who was the basis for Long John Silver was the father of the girl who was the basis for Wendy Darling.

- 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 toffee 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.

- XL: Out of a jiffy and two shakes, it depends what kind of jiffy when finding out which is quicker. Both are units of measuring time. A shake is the time it takes for one step in a nuclear chain reaction to happen, which is about one 10billionth of a second, with a nuclear chain reaction typically taking 50-100 shakes. The term was coined by people at the Manhattan Project and comes from the expression, "two shakes of a lamb's tail", an expression of unknown origin. There are various kinds of jiffy. One is in electronics, where a jiffy is the period of an alternating current power cycle, which is typically a sixtieth or fiftieth of a second. Another is in physics, where a jiffy is the time it takes for light to travel one fermi, which is approximately the width of a proton. Thus a jiffy in physics is father than two shakes, but a jiffy in electronics is slower.

- XL Tangent: Alan has wrongly believed that phrase: "Two shakes of a lamb's tail" is, "Two shakes of a winkle's tale", because that is what his grandmother used to say.

- 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 IX 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, and thus looks better. Big Ben however has an IV for four.

- XL Tangent: The panel do some maths with Roman numerals, which is actually simpler than appears at first. They add 16 by 8, which is XVI + VIII. The simple way is put all the digits in numerical order, the largest on the left, which is XVVIIII. Two "V"s make an "X", so you replaced them, and you get XXIIII, which is 24, the correct answer to the sum.

- XL Tangent: Roman numerals were added to the end of BBC programmes in 1976, with one theory being that it would confuse viewers, and trick people into thinking they were not watching a repeat. Another theory is that it comes from the film industry, because physical film can degrade over time and numeric values can be difficult to read, so the Roman numerals are easier to read.

- 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 an 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.

- XL Tangent: The reverse of the new pound coin was designed as part of a competition. Among thousands of entries, including ones featuring teacups, rain clouds, the London Eye and the Rolling Stones' tongue and lips logo, the winning entry was by 15-year-old David Pierce from Walsall, and his initials appear on the bottom of coin. The design is now on 1.5 billion coins and he won £10,000. Pierce's response to winning was: "Honestly, I'm not too fussed about it all - my friends are more excited than me. It's just something I did once, you know?"

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 high temperatures that cause the tar to belt, along with the bitumen. The bitumen oils in the asphalt rise to the surface, and once the surface cools 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 a slippery road makes no sense, because the skid marks made by the car impossible.

- 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 cartoon, 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)

- XL Tangent: Haydn's Symphony No. 45 is called the "Farewell" symphony because the Hungarian prince Nikolaus the First had gone to his summer palace, so Haydn brought the orchestra but the prince stayed way longer than anyone thought was sensible. Thus, Haydn was asked to drop not such a subtle hint to Nikolaus. Thus, in the final adagio of the Farewell Symphony each musician in turn gets up, snuffs out a candle on his music stand and leaves the room, until all that is left was the two violins. Nikolaus went home the following morning.

- 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
  • Thursday 7th March 2019, 19:15 at BBC Television Centre (James Acaster, Bridget Christie, Joe Lycett)


Show past repeats

Date Time Channel
Saturday 4th April 2020 9:00pm
45 minute version
Wednesday 4th November 2020 9:00pm
60 minute version
Thursday 5th November 2020 2:40am
50 minute version
Monday 18th January 2021 9:00pm
60 minute version
Tuesday 19th January 2021 1:20am
70 minute version
Tuesday 19th January 2021 6:00pm
60 minute version
Thursday 28th October 2021 9:00pm
60 minute version
Friday 29th October 2021 6:00pm
60 minute version

Cast & crew

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
Diccon Ramsay Director
John Lloyd (as John Lloyd CBE) Series Producer
Piers Fletcher Producer
Justin Pollard Associate Producer
Nick King Editor
Jonathan Paul Green Production Designer
Nick Collier Lighting Designer
Howard Goodall Composer
Mat Coward Researcher
Will Bowen Researcher
Andrew Hunter Murray Researcher
Ed Brooke-Hitching Researcher
Jack Chambers Researcher
Emily Jupitus Researcher
James Rawson Researcher
Sarah Clay Commissioning Editor


Joe Lycett hates the Klaxon font

Is this new typeface an improvement?

Featuring: Sandi Toksvig & Alan Davies.

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