This book should have changed mathematics forever

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  • เผยแพร่เมื่อ 16 ก.พ. 2024
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    Modifications to Burgi’s Book
    I made a couple changes to Burgi’s tables to make this video easier to follow. Burgi’s red numbers are scaled by a factor of ten - I removed this in some locations - also his tables didn’t include any decimal places - this notation had not been developed yet. There are no decimal places in his original work - I added the decimal points in some locations for clarity.
    Book Recommendation
    Sections of this video are based on a terrific book by Klaus Truemper - despite it’s terrible cover, it’s a great read with an original viewpoint, and we only covered a small portion here - you can buy a copy on my amazon storefront here: amzn.to/3u2Rt7x
    Special thanks to the Patrons
    Juan Benet, Ross Hanson, Yan Babitski, AJ Englehardt, Alvin Khaled, Eduardo Barraza, Hitoshi Yamauchi, Jaewon Jung, Mrgoodlight, Shinichi Hayashi, Sid Sarasvati
    Welch Labs
    Support on Patreon receive exclusive benefits: / welchlabs
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    References
    The Daring Invention of Logarithm Tables - Klaus Truemper
    The History of Mathematical Tables: From Sumer to Spreadsheets - Martin Campbell-Kelly
    Description of the Wonderful Canon of Logarithms - John Napier
    Jost Bürgi's Aritmetische und Geometrische Progreß Tabulen - Kathleen Clark
    Arithmetic and Geometric Progression Tables - Jost Burgi 1620
  • วิทยาศาสตร์และเทคโนโลยี

ความคิดเห็น • 444

  • @ldx8492
    @ldx8492 3 หลายเดือนก่อน +721

    holy sh** it really is the first engineer's tool! I LOVE the idea that slide rules existed around the birth of modern scientific method (Galileo)

    • @Llucius1
      @Llucius1 3 หลายเดือนก่อน +20

      What if this is not the FIRST engineer's tool , but just ONE of it.

    • @user-lu6yg3vk9z
      @user-lu6yg3vk9z 3 หลายเดือนก่อน +11

      Hello here comes the ancient Egyptians? Ancient Egyptians didn’t have engineering tools to build those pyramids…..hmmm

    • @lucasrinaldi9909
      @lucasrinaldi9909 3 หลายเดือนก่อน

      @@user-lu6yg3vk9z One thing has absolutely no relation to the other.

    • @TwentyNineJP
      @TwentyNineJP 3 หลายเดือนก่อน

      ​​@@user-lu6yg3vk9z Mentally insert the "ALIENS!" meme here

    • @tieegg
      @tieegg 3 หลายเดือนก่อน +5

      It's truly absurd to think ancient people wouldn't do these calculations. It's not like they had phones to distract them or google... or grocery stores.

  • @Houshalter
    @Houshalter 3 หลายเดือนก่อน +430

    Before logarithms there were other tricks to multiply numbers. The babylonians used similar tables to quickly lookup x^2. Using this you can get a*b by calculating ((a+b)^2 - a^2 - b^2)/2.

    • @sachs6
      @sachs6 3 หลายเดือนก่อน +28

      I think they had half square tables directly, so they didn't had to half anything.

    • @Houshalter
      @Houshalter 3 หลายเดือนก่อน +31

      @@sachs6 right. You could even make a ridiculous looking babylonian slide rule that does this with several steps. Each step is just addition, subtraction, or a function of a single value. The kind of things slide rules do.

    • @caspermadlener4191
      @caspermadlener4191 3 หลายเดือนก่อน +20

      This is a bit slow. It is quicker to calculate ab as ((a+b)/2)²-((a-b)/2)²

    • @Llucius1
      @Llucius1 3 หลายเดือนก่อน +4

      @@caspermadlener4191 Not if the calculation is more complicated , it is kind of like using the calculator.

    • @djmips
      @djmips 3 หลายเดือนก่อน +6

      And it's important to realize that the Babylonians did this perhaps 4000 years ago!!

  • @Shad0wImp
    @Shad0wImp 3 หลายเดือนก่อน +224

    There's a wonderful little book called The Calculus: A Genetic Approach, written by Otto Toeplitz, which essentially starts with an in-depth discussion of exactly what you've covered here. So nice to see Burgi being mentioned! Otto would've loved this video. Thanks for making it.

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน +27

      Woah cool - haven't heard of this -> just ordered a copy. Thanks!

    • @granand
      @granand 3 หลายเดือนก่อน +1

      Can I ask dumb questions, are logarithms needed with scientific calculators available online ?

    • @DoNotBeASIMP
      @DoNotBeASIMP 3 หลายเดือนก่อน +7

      ​@@granandNo, you don't need to learn logarithms. Also second degree equations are useless. Geometry is useless. Everything you learn at school is useless! Make sure to listen to crappy influencers who have never built anything in their lives, but yet are entitled enough to say everything is not needed and a waste of your time. I hope you have two neurons to see the irony of my comment.

    • @JustAThought01
      @JustAThought01 3 หลายเดือนก่อน +4

      @@DoNotBeASIMP, being able to remember is useful. Being able to think is even more useful.

    • @pavelperina7629
      @pavelperina7629 3 หลายเดือนก่อน +2

      @@granand Basically they are not needed for multiplication and division when you have calculator. But they are needed for exponential growth and decay. But since we have chatgpt you can ask how to solve these problems (and blindly trust that answer is correct)

  • @programmer1356
    @programmer1356 3 หลายเดือนก่อน +73

    I love the use of dots for repeated digits

  • @FloydMaxwell
    @FloydMaxwell 3 หลายเดือนก่อน +104

    When I studied engineering in the 80s, I had a circular slide rule. Awesome video.

    • @jvin248
      @jvin248 3 หลายเดือนก่อน +4

      I have a small salad plate sized circular slide rule that maps out to a linear slide rule nine feet long.

    • @jeffweber8244
      @jeffweber8244 3 หลายเดือนก่อน +4

      When I studied engineering in the 80s, I had a TI-41CX.

    • @gary_rumain_you_peons
      @gary_rumain_you_peons 3 หลายเดือนก่อน +1

      I had a circular one (as well as the more traditional sliding one) in the early 70s. It fits in the palm of my hand with my fingers being able to hold it.
      But, by 1976, I had a TI electronic calculator. I still have the circular slide rule (and the sliding one but some of the useful white part has broken off from the bamboo wood ).
      Lost the TI calculator ages ago.

    • @FloydMaxwell
      @FloydMaxwell 3 หลายเดือนก่อน

      @@gary_rumain_you_peons I switched to the Sharp calculators that had a great 49 char LCD AND a "playback" feature so you could check your formula (or reuse it, as it could draw from 6 memory locations). It was my last, and very best, calculator. My circular calculator got cracked because I carried it in my back pocket and sat on it frequently.

    • @skysurfer5cva
      @skysurfer5cva 3 หลายเดือนก่อน +2

      @@jeffweber8244 Hewlett-Packard made the 41CX (i.e. HP-41CX), not TI. My HP-41CX still works, although I usually use an HP-42S.

  • @walterbrown8694
    @walterbrown8694 3 หลายเดือนก่อน +72

    Still have my 70 year old Post Versalog slide rule and books of logarithm tables I used in engineering school in the early 50s. My work in radar and military electronics systems used logarithmic measurement techniques extensively also. ( Y db = 10 log X ) And, neither needed batteries or solar power to operate.

    • @charlesbrowne9590
      @charlesbrowne9590 3 หลายเดือนก่อน +9

      I remember my dad giving me a slide rule and book of logarithms in 1966. I lived in Cleveland where was the Chemical Rubber Company (CRC). The CRC put out handbooks on math, physics, and chemistry. They would donate unsold copies of ‘the CRC’ to local school children. I would peruse the pages of the handbooks wanting so much to learn what all the symbols and formulas meant.
      I too wound up in radar and military electronics engineering.

    • @camgere
      @camgere 3 หลายเดือนก่อน +2

      Was Phasor Analysis important to early radar work? Radar did such a nice job of knocking Nazi bombers and fighters out of the sky. In school it seemed like such a cool way of solving linear time invariant control systems. (Everything is magnitude and angle (frequency dependent)).

    • @PR-fk5yb
      @PR-fk5yb 3 หลายเดือนก่อน +3

      Of course you used solar power... otherwise you would have been in the dark!😅

    • @orang1921
      @orang1921 3 หลายเดือนก่อน +2

      holy moly, you're old man. stay with us for about 5 years

  • @ericlotze7724
    @ericlotze7724 3 หลายเดือนก่อน +25

    6:42 THIS, and the independent co-discovery of it (at least to an extent) afterwards is why not only Open Source Work, but also even documenting unfinished projects is so huge.
    Even something you think is just a neat trick can be EXTREMELY useful for someone else.

  • @yanntal954
    @yanntal954 3 หลายเดือนก่อน +99

    I'd love a video on prosthaphaeresis, the original way to do complex operations using a table 😊
    It's so much nicer in my opinion just vecause trig functions are so classical!

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน +14

      Yeah I've bumped into this a few times - will but this on the idea list!

    • @JohnVKaravitis
      @JohnVKaravitis 3 หลายเดือนก่อน

      "prosthaphaeresis"???? Do you kiss your mother with that mouth???

    • @solconcordia4315
      @solconcordia4315 3 หลายเดือนก่อน

      @WelchLabsVideo
      There was an *EXACT* formula for computing an arbitrary digit of the number pi in base 16 (hexadecimal base.) Can one make a geometric explanation of why that formula works (perhaps by using areas within and lengths of a unit circle and the Babylonian quarter of squares tables for computing multiplicative products) ?
      ab = 0.25 (a+b)^2 - 0.25 (a-b)^2
      Maybe the quadrants of the unit circle have some relationship to do with the hexadecimal base ? What is it ?

    • @ok-hv1or
      @ok-hv1or 3 หลายเดือนก่อน

      ​@@solconcordia4315can you share this pi formula?
      The formula you wrote is just a multiplication formula

    • @usernamenotfound80
      @usernamenotfound80 3 หลายเดือนก่อน

      @@ok-hv1or It's the Bailey-Borwein-Plouffe formula.

  • @TranquilSeaOfMath
    @TranquilSeaOfMath 3 หลายเดือนก่อน +21

    Nice video. I've studied the history of logarithms, but was not aware of Burgi's work. Thank you for publishing this.

  • @maxmn5821
    @maxmn5821 3 หลายเดือนก่อน +66

    An even easier way to remember how to multiply and divide on the slide rule is to remember that scales establish a ratio which stays constant everywhere on the scale. a/b=a‘/b‘. By choosing one of them to be 1, the calculation becomes mere multiplication or division.
    By the way, there are very simple circular slide rules with just two scales - inner and outer. Target customers are accountants/merchants.
    From now on I’ll recommend struggling teens to first watch this video and then 3b1b on logarithms. It‘s often easier to understand things by taking inventors perspective.
    If I‘m allowed to compare - it‘s like Kathy Loves Physics but for math. Thanks for this very nice video.

    • @douglasmagowan2709
      @douglasmagowan2709 3 หลายเดือนก่อน +2

      Pilots used to use circular slide rules (the e6b flight computer) right up until the invention of the iPad.

    • @HMPerson2
      @HMPerson2 3 หลายเดือนก่อน +2

      might I also recommend vihart's mini-series on dragons, fractals, and logarithms

    • @lucasrinaldi9909
      @lucasrinaldi9909 3 หลายเดือนก่อน +1

      Now I feel stupid. I have no idea what that symbol above the letters means in mathematical notation.

    • @chrisashdown1484
      @chrisashdown1484 3 หลายเดือนก่อน

      They still use them or at least always carry one in their bag and know how to use them, electronics have a bad habit of failing just when you need them which is not good at 30,000 feet@@douglasmagowan2709

    • @MattMcIrvin
      @MattMcIrvin 2 หลายเดือนก่อน

      @@lucasrinaldi9909 In this case, it just means "the other one". a and a' would be two different values on the same scale, b and b' two different values on the other scale. Sometimes it means other things.

  • @ronniechilds2002
    @ronniechilds2002 3 หลายเดือนก่อน +7

    What brains those guys had! Just unfathomable.

  • @briankirk4685
    @briankirk4685 3 หลายเดือนก่อน +36

    I used to own a log and trig table book, also referred to as math tables. Used it in high school. Did math like shown in this video but base 10 instead. It was a cheaper book, so it only had a 4 place mantissa. Used a sliderule extensively in a couple navy courses. Wasn't until 1977 that calculators got cheap enough to replace sliderules and math table books.

    • @OKOKOKOKOKOKOK-zn2fy
      @OKOKOKOKOKOKOK-zn2fy 3 หลายเดือนก่อน +5

      That's when math education in America collapsed.
      We left the slide rule and lost a generation of mathematicians.
      The teachers who came up on slide rules didn't know how to teach "new math" and the students didn't get it either.

    • @puppergump4117
      @puppergump4117 3 หลายเดือนก่อน +1

      @@OKOKOKOKOKOKOK-zn2fy If you really know math and aren't just dependent on tools, it's easy enough to teach. For me, rather than the intuitive crap they sell, I can only learn it by writing it in code. They've lost the logic and the patterns and are stuck with their tools and formulae.

    • @rogerphelps9939
      @rogerphelps9939 3 หลายเดือนก่อน +3

      Yes. I remember using log and trig tables at school and then a slide rule at university. I still have my slide rule! I ended up in sonar.

    • @user-sk8ye1su9f
      @user-sk8ye1su9f 3 หลายเดือนก่อน

      In India students still use log and trig tables in their examinations.@@rogerphelps9939

  • @talmanl
    @talmanl 3 หลายเดือนก่อน +6

    To see where the notion of slide rule ultimately went, check out Thacher's Cylindrical Slide Rule. (I actually used one at work in the early Sixties.)

  • @MasterHigure
    @MasterHigure 3 หลายเดือนก่อน +23

    I remember my high school math book said the first logarithm table was made with a base of 1.0001, but that mathematicians figured out 10 was a more sensible base (which may be a simplification, but base 10 is what became big). I had basically forgotten that little tidbit until this video reminded me.

    • @trueriver1950
      @trueriver1950 3 หลายเดือนก่อน +11

      From a strictly mathematical point of view (rather than practical usage) e is the most obvious base. If I remember rightly that's what Napier used in his first published set of log tables.
      e turns up all over mathematics, whereas 10 is not really mathematical at all, it's just an artefact of our chosen notation for interests and decimal fractions.

    • @MasterHigure
      @MasterHigure 3 หลายเดือนก่อน +4

      @@trueriver1950 Sure. But the angle in this video is engineers and actual calculations, not mathematical calculus and analysis. 10 is better in that case, although the difference is marginal, especially to anyone who uses them several times a day.

    • @pavelperina7629
      @pavelperina7629 3 หลายเดือนก่อน

      @@trueriver1950 If you use base 1.0001 (1+10^-4), number e is close to 10000th entry 🙂Because e=(1+1/x)^x for x approaching infinity and 10000th entry is (1+1/10000)^10000=1.0001^10000.
      Napier used 0.999999 or something like that - same trick which burgi used: you can rewrite number and subtract 1/1000000 (burgi used adding 1/10000). Maybe that's why Burgi is mention in the video - napier work was less intutive and also his table started by 90 degree and each entry was one minute lower with corresponding sine of angle (maybe cosine and tangens too, i don't remeber).

    • @tiranito2834
      @tiranito2834 2 หลายเดือนก่อน

      @@MasterHigure if the focus is engineering then e and 1.0001 are still more useful than 10 lol.

    • @MasterHigure
      @MasterHigure 2 หลายเดือนก่อน

      @@tiranito2834 Not at all. Because you can eyeball 10-logarithms with a minimal amount of practice, way easier than you can eyeball e-logs or 1.0001-logs (for instance, even _without_ practice, I can tell at a glance that the 10-log of 3145 is about 3.5). The two other logarithms take a lot more practice, or alternatively, they require a separate step of some mental multiplication with a memorized constant. No, 10 is much more convenient for practical use.

  • @charlessmyth
    @charlessmyth 2 หลายเดือนก่อน +3

    Back in the day of my day, Log Tables and/or the Slide Rule was what you had available to use. Calculators had just come on the scene and were not allowed for exams, etc.. :-)

  • @pentachronic
    @pentachronic 3 หลายเดือนก่อน +5

    We used 4-figure tables in highschool. Had logs, sin/cos/tan and antilog etc. Good memories.

  • @NphiniT
    @NphiniT 3 หลายเดือนก่อน +13

    Welch Labs! Welcome back man!!

  • @user-fc7is6jo2e
    @user-fc7is6jo2e 3 หลายเดือนก่อน +1

    Thank you for sharing this. I am also commenting to help your brilliant channel with the algorithm so that more people see it.

  • @dasvanalo3504
    @dasvanalo3504 3 หลายเดือนก่อน +13

    A really interestic topic, a cool book, and the best explanation on log tables i have seen!

  • @iteerrex8166
    @iteerrex8166 3 หลายเดือนก่อน +73

    I have a suggestion to most everyone, to relearn logarithms. Everyone uses it all the time (correctly), but because of calculators, they don’t have a good grasp of it.

    • @iyziejane
      @iyziejane 3 หลายเดือนก่อน +1

      Maybe if the goal is to build more intuition about logarithms, it's good to mentally calculate floor(log x) i.e. the largest integer we can raise the base of the log to and still be less than x.

    • @r2d277
      @r2d277 3 หลายเดือนก่อน +1

      Can you give an example of that uses of logarithm? I can't see so clearly this commom use... thanks in advance!

    • @iteerrex8166
      @iteerrex8166 3 หลายเดือนก่อน

      @@r2d277 3blue1brown has at least 3 good videos about logs.

    • @iteerrex8166
      @iteerrex8166 3 หลายเดือนก่อน

      @@r2d277 I tried to tell you about some content but it got removed, twice 🤷‍♂️

    • @iteerrex8166
      @iteerrex8166 3 หลายเดือนก่อน

      @@r2d277 3blue1brown, log

  • @norude
    @norude 3 หลายเดือนก่อน +19

    so it's the logarithmic ruler, but in book form

    • @norude
      @norude 3 หลายเดือนก่อน +4

      in English it's also called the slide rule

    • @pavelperina7629
      @pavelperina7629 3 หลายเดือนก่อน +1

      @@norude in czech slide rule is what you call calipers in english :-)

  • @SanjeevScienceTV
    @SanjeevScienceTV 2 หลายเดือนก่อน +10

    isn't it logarithms?

    • @sebastiangudino9377
      @sebastiangudino9377 5 วันที่ผ่านมา +1

      Yup, this is a logarithmic book, but that term was very young, still not related to exponentiation. It was the name given by Napier to the mapping between a geometric and arithmetics series. The arithmetic series giving you an "Arithmetic Number" aka "Logos Arithmos" in greek. So -> "Logarithmos" -> "Logarithm"

  • @holykoolala
    @holykoolala 3 หลายเดือนก่อน +56

    Where did you get that paper copy of the original book? Is there a good public domain scan of the original book available?

    • @michaeldamolsen
      @michaeldamolsen 3 หลายเดือนก่อน +8

      if you google the following (including the quotes) you should find it: "Bürgi, Jost:Aritmetische vnd Geometrische Progress Tabulen"
      (note that the spelling "mistakes" are in the page you are trying to find, so don't feel tempted to correct 'vnd' to 'und' etc.)

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน +35

      Printed it myself from this pdf: bildsuche.digitale-sammlungen.de/index.html?c=viewer&bandnummer=bsb00082065&pimage=8&v=100&nav=&l=de

    • @puppergump4117
      @puppergump4117 3 หลายเดือนก่อน +5

      You can find literally anything by typing the name and .pdf at the end

    • @trueriver1950
      @trueriver1950 3 หลายเดือนก่อน +8

      ​@@michaeldamolsen pedantic note: at the time of original publication what we now think of as the letter V also served as our letter U. So it's only a spelling mistake from a modern perspective.
      But you are quite right, you have to keep the archaic spelling or the search engine gets muddled...

    • @trueriver1950
      @trueriver1950 3 หลายเดือนก่อน

      ​@@puppergump4117 must try that...
      Millionpounds.pdf
      SaturdaysLottoNumbers.pdf
      Naaaah, doesn't work ...
      The last one nearly works, and you don't actually need the .pdf -- trouble is it gives you last Saturday's number which is not quite as useful

  • @dinninfreeman2014
    @dinninfreeman2014 2 หลายเดือนก่อน +1

    That circular design was almost certainly inspired by Raymond Llull and his combinatory wheels

  • @bubbahottep8644
    @bubbahottep8644 3 หลายเดือนก่อน +3

    So, logs. Fascinating.

  • @TheRealInscrutable
    @TheRealInscrutable 3 หลายเดือนก่อน +7

    This reminds me of the log tables I was taught to use along with a slide rule in 7th grade. Oh so many years ago.

  • @nlaughton
    @nlaughton 3 หลายเดือนก่อน +2

    Fantastic video! Just pulled out my grandfather's old slide rule (he was an architect). I'd love to get my hands on a copy of the original tables like you show in your video (I assume you printed out a copy for the video).

  • @caomunistadoggo4129
    @caomunistadoggo4129 22 วันที่ผ่านมา

    Oh, I would love to acquire a copy of this book. SO BEAUTIFUL

  • @genovo
    @genovo 3 หลายเดือนก่อน +1

    The Space Shuttle was built with the slide rule

  • @roliveira2225
    @roliveira2225 16 วันที่ผ่านมา

    Excellent!

  • @SirWhiteRabbit-gr5so
    @SirWhiteRabbit-gr5so 22 วันที่ผ่านมา

    My high school physics class was slide-rules and math tables. Even in college math tables were referenced as-much as the new handheld calculator.

  • @user-ze6fs5ui6h
    @user-ze6fs5ui6h 3 หลายเดือนก่อน +1

    Thank you! It would be also interesting to see a more detailed analysis, of how many elementary operations you save using these tables. For instance, it takes time just to find the corresponding logarithm in the book, so it is not so obvious how strongly does it speeds up the process.

    • @chessdominos
      @chessdominos 3 หลายเดือนก่อน

      Fair point.
      Let's immagine our self to multiply distinct numbers.
      Number A by number B both with 10 digit.
      We choose 10 times A, B.
      In the usual way we must perform 100 multiplications and 90 addictions.
      By using this method with
      look up table we perform only 10 addiction.
      We may conclude as well then although not perfect is less prone to mistakes.

  • @kevinnunn2653
    @kevinnunn2653 3 หลายเดือนก่อน +2

    Loved this video EXCEPT all the times the narrator said “math” when they clearly meant “arithmetic.”
    Using a logarithmic system to simplify computation IS math. Reading a graph IS math. Finding the relationship between two objects IS math.
    Other than that quibble, solid stuff.

  • @HotelPapa100
    @HotelPapa100 3 หลายเดือนก่อน +2

    Briggs logarithms used to be called "Bürgi's logarithms" in Switzerland...

  • @_spartan11796
    @_spartan11796 3 หลายเดือนก่อน +1

    Holy crap! 2 videos within 2 weeks?!

  • @juwright1949
    @juwright1949 3 หลายเดือนก่อน

    Excellent! We build upon the shoulders of those that went before us! How true in mathematics / philosophy. Well done.

  • @NegatorUK
    @NegatorUK 3 หลายเดือนก่อน +9

    At school in the 70s we were taught how to use logarithms to make our own slide rule out of cardboard - a very easy process. Is that still done ?
    If calculators have taken over then kids should have to at least breadboard out their own simple calculator imho ;-)

    • @IMBlakeley
      @IMBlakeley 3 หลายเดือนก่อน +1

      I still have my slide rule from my 70s maths classes, not sure I could use it now without some research.

    • @ZygonesBzygones
      @ZygonesBzygones 3 หลายเดือนก่อน +1

      in the 80s we still had giant slide rules on the walls in our maths class rooms, but we skipped the chapters on their use - I later accidentally "rediscovered the slide rule" playing with a few sheets of logarithmic paper, observing that twice the 1 to 10 bit amounted to the length of the 1 to 100 bit... and actually feeling quite dumb that I had to think about _why_ that was...
      and I did not immediately connect my "discovery" (half a millennium too late, but still) to those giant wall slide rules, because they had multiple bars / scales and I had always assumed these things were way too complex for me to master

    • @squirlmy
      @squirlmy 3 หลายเดือนก่อน +1

      Well they now have smartphones, not just calculators, and with a download they can match the most sophisticated "scientific calculators". I'm glad to see the end of the tyranny of TI-86 in the US, but, we're getting to the point where a kid can just verbally ask an AI what the solution is, without any conception of calculations at all.

    • @pavelperina7629
      @pavelperina7629 3 หลายเดือนก่อน

      I studied elementary school from 1987 in Czechia, graduated in 2004. I know slide rule only because it was magical item that was among some pencils, drafting tools, compasses and rulers in a drawer of my table. We basically learned powers and logarithms as a given tool, we learned how to simplify equations and how to calculate interests. But I wasn't able to apply them correctly on some example with radioactive decay where exponents were too big for straightforward solution on calculator. That was at middle education (is it called high school in US?) Then I used them at university applied as exponential attenution, conversion to decibels and back and that's basically all.
      Conversion of multiplication to addition and how to get square root was something I learned asking my mother about slide rule. Then recipe at uni was basically to convert stuff to decibels per unit lenght, mutliply by length, convert it back. Or voltage on capacitor vs time. University was actually when I used logs.

  • @glennlopez6772
    @glennlopez6772 3 หลายเดือนก่อน

    We learnt this in high school!
    And learned to appreciate those before us who worked on this.

  • @bennybaker4926
    @bennybaker4926 หลายเดือนก่อน

    Very interesting history.

  • @MrPSaun
    @MrPSaun 3 หลายเดือนก่อน

    Volvelles are awesome! I have a collection of facsimiles that calculate everything from the day of the week and the positions of the stars to the hexachords along the circle of fifths. These little paper computers are phenomenal examples of human ingenuity. I could gush about them for hours.

  • @ZapOKill
    @ZapOKill 3 หลายเดือนก่อน +13

    the title confuses mathematics with calculation

    • @whimpypatrol5503
      @whimpypatrol5503 3 หลายเดือนก่อน

      So many of the things derived in finite math can't be calculated because the tabulation evolves to many steps even for the fastest digital computers in existence or even conceptually imagined. A computational algorithm or approximation method sometimes helps. Quantum computers may change that. Even they will require their own algorithms.😢 But it's not like business managers or engineers will ever use much math anyway.

  • @infinitelink
    @infinitelink 3 หลายเดือนก่อน

    If you lookup the methods for getting square roots before calculators in the west, you quickly discover... there's a reason the square-root symbol looks like the symbol used for long division (differentiated in look as though a "v" is fused to its initial forward-slanting line)...
    It's not that it's a form of division so much as the signs are indicative of relation.

  • @blackartist7
    @blackartist7 3 หลายเดือนก่อน +2

    Wow this reminds me the round device Dr. Strangelove used. Is it the same thing? Circular slide ruler?

  • @TwoMarlboro
    @TwoMarlboro 3 หลายเดือนก่อน

    This disc later evolved into the Nipkow disc, which in turn became a famous TV price in the Netherlands.

  • @mihaleben6051
    @mihaleben6051 8 วันที่ผ่านมา

    Oh man i love multiplication.
    Especially by 10^x where x is a positive number
    My favorite rule is a*b+a*c=a(b+c) since the sum of b+c being equal to 10^|x| is non zero

  • @franciscocasillas8233
    @franciscocasillas8233 3 หลายเดือนก่อน

    You made it so we don't have to see the Ad. Out of respect for your work, I sat through it. Thanks for sharing.

  • @clementdellaiera3144
    @clementdellaiera3144 3 หลายเดือนก่อน

    Very nice video! A question : does anybody has any idea as to how the book was printed? It seems hand made, and I was wondering how one would obtain such a nice result

  • @rbfreitas
    @rbfreitas 3 หลายเดือนก่อน

    Great video

  • @MajkaSrajka
    @MajkaSrajka 2 หลายเดือนก่อน

    Reminds me of how Nintendo64 and Super Mario 64 "calculated" sin(x) (and cos(x) by looking them up and how due to hardware reasons surprisingly efficent it was when compared to other alternative/more modern implementations. There should be a quite interesting video on that here on YT.

  • @ryanbeard1119
    @ryanbeard1119 3 หลายเดือนก่อน

    So are log rythems more, synthetic or we just didn't have the rapid commuting power to exploit them

  • @ernestuz
    @ernestuz 3 หลายเดือนก่อน +5

    Basically a table of logarithms base 1.0001, I suppose he chose that base to simplify the operations to calculate the table, that are just shifts and additions. Very clever.

    • @meowtheroflearning2320
      @meowtheroflearning2320 3 หลายเดือนก่อน +1

      Nope, it is basically approximating e as a base. For example (1.0001)^10000 ~= 2.718... ~= e.

    • @pavelperina7629
      @pavelperina7629 3 หลายเดือนก่อน

      @@meowtheroflearning2320 No, e was found like 120 years later. But it's a nice "coincidence" that it appears as 10000th entry.

  • @PinakiGupta82Appu
    @PinakiGupta82Appu 3 หลายเดือนก่อน +1

    Looks like a natural log table book. However, here we see the Importance of publishing critical works as open-source.

  • @truthinkr2931
    @truthinkr2931 3 หลายเดือนก่อน +1

    very clever!😉

  • @Metastate12
    @Metastate12 3 หลายเดือนก่อน

    Mind.Blown.

  • @outtakontroll3334
    @outtakontroll3334 3 หลายเดือนก่อน +1

    just consider how difficult it used to be to calculate, and be happy it is so easy now.

  • @stokedfool
    @stokedfool 3 หลายเดือนก่อน

    Very interesting. Thank you for the insights.

  • @rishabhbhati5456
    @rishabhbhati5456 3 หลายเดือนก่อน

    Please make a video on your story like what you do and were doing.

  • @karius85
    @karius85 3 หลายเดือนก่อน +14

    "Should have changed mathematics forever" is a crazy thing to claim. He could have been the inventor of logarithms. A contemporary beat him to it. Meh....

    • @riley1636
      @riley1636 3 หลายเดือนก่อน +5

      To be fair, his method would likely have people widely using slide rules a fair bit earlier.

  • @gcewing
    @gcewing 3 หลายเดือนก่อน +3

    I wonder what terminology we would have got if he had published first. Instead of a log function, would we have a red function?

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน +3

      Fun question! I don't know - but I do like the name red numbers more than logarithms.

    • @watchm4ker
      @watchm4ker 3 หลายเดือนก่อน

      Unlikely. You'd have a terminology crash with accounting, and as the video hints at, the mathematical functions being described have a *much* broader reach than a multiplication aid.

  • @DekuStickGamer
    @DekuStickGamer 3 หลายเดือนก่อน +7

    Man if he wasn't making clocks and focused on science - we'd have flying cars by now

    • @ZygonesBzygones
      @ZygonesBzygones 3 หลายเดือนก่อน +1

      no

    • @watchm4ker
      @watchm4ker 3 หลายเดือนก่อน

      We *have* flying cars, now. They're expensive as hell, and still need a pilot's license.

    • @thebitterfig9903
      @thebitterfig9903 3 หลายเดือนก่อน

      Right, but perhaps because he worked on clocks, I have a pair of watches with slide rule bezels.

    • @costakeith9048
      @costakeith9048 3 หลายเดือนก่อน

      Clockmaking was at the forefront of science and engineering at the time, the skills developed allow the invention of a whole plethora of scientific instruments, laid the groundwork for advances in astronomy and navigation, and gave birth to the machine tools that allowed for the scientific revolution.

  • @tiranito2834
    @tiranito2834 3 หลายเดือนก่อน +2

    Well, lookup tables are used all over the place in high performance computations, so it did change mathematics and engineering forever. It could be argued that it was way ahead of its time I suppose.

  • @Innomen
    @Innomen 3 หลายเดือนก่อน

    I feel like this sort of thing will eventually allow us to move around inside pi and find any number in it. Like GPS but for Pi. (PPS?)

  • @eonasjohn
    @eonasjohn 3 หลายเดือนก่อน

    Thank you for the video.

  • @maxfred1696
    @maxfred1696 3 หลายเดือนก่อน +5

    Why was 1.0001 chosen as the base?

    • @PalladinPoker
      @PalladinPoker 3 หลายเดือนก่อน +1

      I assume for high precision with integer powers.

    • @davidvomlehn4495
      @davidvomlehn4495 3 หลายเดือนก่อน +5

      The math works out for any basis, but 1.0001 is a good compromise between precision and a set of tables small enough to be publishable. In the real world, we rarely need even three digits of precision. Outside of the real world, I work with people who compute spacecraft trajectories. They need a lot more than three digits of precision. Fortunately, that wasn't much of a consideration 400 years ago.

    • @Llucius1
      @Llucius1 3 หลายเดือนก่อน

      Perhaps this number give the enough amount of reference vs effort to time ratio , imagine calculating all that by hand , that is really some good work.

    • @trueriver1950
      @trueriver1950 3 หลายเดือนก่อน +1

      He calculated powers rather than logarithms. To get a table you can calculate either. It is a lot easier to calculate powers than logs.
      To get any precision by repeated multiplication of powers you need a number close to 1.
      If he used base ten his table would tell us the black number 10 has the red number 1, 100 is 2, and so on.
      The other thing is that having spotted that he wanted a number close to 1, having one further digit of 1 makes manual multiplication that much easier. Tedious but easy.
      How many zeros? The more zeros before that final 1 the better the accuracy; but with two costs: the numbers take longer to calculate, because you need to do more multiplications, and the book becomes correspondingly thicker and more expensive to print.
      I guess he thought that a precision of one in 10^5 was a sensible trade off

    • @brendawilliams8062
      @brendawilliams8062 3 หลายเดือนก่อน

      607009099 times 121

  • @samueldeandrade8535
    @samueldeandrade8535 3 หลายเดือนก่อน +1

    Man, Welch Labs is such a great youtuber. Definitely deserves more and more.

  • @nanamacapagal8342
    @nanamacapagal8342 3 หลายเดือนก่อน +6

    Just asking, is the "log" in "logarithm tables" the same "log" in "logbook" and "log in"?

    • @nathanoher4865
      @nathanoher4865 3 หลายเดือนก่อน +33

      No, it’s got a different origin.
      Logarithm was coined by its inventor John Napier from Ancient Greek λόγος (lógos) meaning word and αριθμός (arithmós) meaning number.
      Logbook referred to a book in which ships recorded their speed for navigation purposes. They got the name from the device used to record speed, the chip log. It was a piece of wood tied to a roll of string that was dropped into the water. The rate at which the string was unwound was used to measure speed.
      Logbook now refers to a record of anything stored in written media.
      The chip log got its name from the fact that the drag (the piece of wood that gets dragged by the water) is a simple piece of wood that is chipped off from a log.
      Log in this sense comes either from Old Norse lóg/lág meaning fallen tree, which itself comes from the verb liggja, meaning to lie (on the ground/a surface); or it came from Norwegian låg, also meaning fallen tree.
      “Log in” is a phrasal verb constructed from the fact that when one accesses a computer account, one is adding an entry into a log. Log in the sense of an append-only sequence of records written to file was probably derived from logbook by analogy. Note that logbook as in a record of a vessel’s progress or as a general written record was already being shortened to log long before computers.
      Logarithm came first (John Napier introduced the term in New Latin as logarithmus) in 1614. Logbook was first attested in nautical records in the 1670s. Log in was first used in 1963 by the MIT Computation Center, in reference to people time-sharing their mainframes.

    • @nanamacapagal8342
      @nanamacapagal8342 3 หลายเดือนก่อน +3

      @@nathanoher4865 aww, pretty sad they don't share the same root
      well at least we know navigators were using both logs quite a lot in the 17th century

    • @alfranco918
      @alfranco918 3 หลายเดือนก่อน +3

      A ship compass and ship’s log were used to track direction and speed. Then a traverse board was used to keep track of those values for the four hours of a watch. At the end of four hours, the data was entered into the logbook. Then started over for. The next four hour watch. (I read the Aubrey-Maturin series of books.)

    • @gary_rumain_you_peons
      @gary_rumain_you_peons 3 หลายเดือนก่อน

      A captain's log is commonly found in the chamber pot in a captain's cabin. A cabin boy would check daily if there was a log in it. If there was, he would empty the log, called a log out. He would then inform the ship''s doctor who would record it in his log book. This was the doctor's log.
      A doctor's log is commonly found in the ...

    • @nathanoher4865
      @nathanoher4865 3 หลายเดือนก่อน

      @@nanamacapagal8342 Yep, I can’t imagine how much time it took to plot out routes without computers!

  • @granddefectus4602
    @granddefectus4602 3 หลายเดือนก่อน +5

    Haven't seen this channel in a while

  • @ianmichael5768
    @ianmichael5768 3 หลายเดือนก่อน +2

    Somewhat sad that these figures have previously been calculated. Would have like to take a stab at computing them by hand.
    That being said, I appreciate the monumental efforts of past generations to accelerate our calculations. Leading us to future questions and constructs.

  • @bahaiwebsites
    @bahaiwebsites 3 หลายเดือนก่อน

    Awesome! No downside

  • @WeirdInfoTV
    @WeirdInfoTV 3 หลายเดือนก่อน +1

    Did you just trick me into learning logs?

  • @briankleinschmidt3664
    @briankleinschmidt3664 2 หลายเดือนก่อน +1

    I'm about to fix math and get my Nobel prize. Here's a hint - division by zero is defined as the null set - the set with no numbers, but, you can put any number in a division by zero and it checks out. Division by zero isn't the set with no numbers. It is the set with ALL numbers. That is why the universe has apparent motion - it reached a division by zero error and exploded.

  • @jonrjd912
    @jonrjd912 3 หลายเดือนก่อน

    whats a formid yield book?

  • @smackastan5697
    @smackastan5697 3 หลายเดือนก่อน

    What kind of person calculated all of those numbers. It must have been soul crushing work

    • @smackastan5697
      @smackastan5697 3 หลายเดือนก่อน

      What? All not to publish it????

  • @tim_allen_jr
    @tim_allen_jr 3 หลายเดือนก่อน

    Interesting a program could be written to turn the wheel and find the answer seamlessly.

  • @CCoburn3
    @CCoburn3 3 หลายเดือนก่อน +2

    OK. So you have what is essentially a table of logarithms. Welcome to the slide rule age.

    • @watchm4ker
      @watchm4ker 3 หลายเดือนก่อน

      In a couple of decades, perhaps.

  • @philkirshenbaum8867
    @philkirshenbaum8867 3 หลายเดือนก่อน +1

    Your videos on Logarithms have inspired me to create my own Napier tables.

  • @Zcon18
    @Zcon18 3 หลายเดือนก่อน +1

    After 2 and 1/2 minutes my guess is that this will be about slide rules

  • @TheStickCollector
    @TheStickCollector 16 วันที่ผ่านมา

    They should have gone over this in school or something to make it more interesting. Would be nice to see the progression of math over time.

  • @rodschmidt8952
    @rodschmidt8952 3 หลายเดือนก่อน

    I want a copy of this book that will fit into my shirt pocket

  • @alanjameson8664
    @alanjameson8664 3 หลายเดือนก่อน

    Old guy here. I have a graphical table of logarithms-- read it like a slide rule; quick and easy. Never did care for the log-log slide rules that were the standard in the US; prefer Darmstadt rules. One formula that was always useful: log (a to the x power) = x log a. Also note that electronic calculators do not actually do the operations that are keyed in; they use electronic functions to simulate them. Because of that one can do a string of multiplications and divisions of a number, then reverse the sequence and come up with a number different from the original one. It was always difficult to hammer an understanding of significant figures into students' heads, but with the advent of electronic calculators (which display numbers to as many places as their displays will accommodate) it has become nearly impossible.

  • @user-ic7ww4lo1m
    @user-ic7ww4lo1m 3 หลายเดือนก่อน +2

    Is this the basis of a 'slide rule' ?
    I never understood it but your video reminds me of Dad trying to explain how to use one back in the '70's.
    (never mind, I though this before you were half way through the video where you made exactly that point. interesting video)

    • @ReedHarston
      @ReedHarston 3 หลายเดือนก่อน

      He has another video that is just about the logarithms book and the slide rule.

    • @thomasgreene5750
      @thomasgreene5750 3 หลายเดือนก่อน +2

      Yes. The numbers between 1 and 10 engraved on a slide rule are scaled along the rule in proportion to their base 10 logarithms. When you slide one scale along another, the combined length is the sum of the logarithms of the two numbers. Because log(ab) = log(a) + log(b), the number under the index on the sliding scale is ab.

  • @shevek5934
    @shevek5934 3 หลายเดือนก่อน

    Is this just the short version of the 20 minute video you posted a few days ago?

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน +3

      More of a prequel!

  • @garysimpson7326
    @garysimpson7326 3 หลายเดือนก่อน +4

    Addition of logarithms was the basis for the slide rule. What am I missing?

    • @trueriver1950
      @trueriver1950 3 หลายเดือนก่อน

      What you are missing is that the first logs were all integers, because instead of starting from a number and finding the log, he started with a number very close to one as the base, and calculated what the number would be whose log works be 1, then the number with the log of 2 by squaring it, and so on
      The thought that is different from every log table since Napier is that he calculated what were would call the antilogs not the logs, and insisted that all the logs works be integers because that makes calculations of the antilogs easy

  • @kellymoses8566
    @kellymoses8566 7 วันที่ผ่านมา

    The progress of math and science was really held back by how often people kept things secret.

  • @obiwanpez
    @obiwanpez 3 หลายเดือนก่อน +1

    Me: "Hey, this looks like a fun video... WAIT. WHO made this???"
    Welcome back! I have been telling all of my precalc students about your Imaginary Numbers Are Real series.

  • @Ggdivhjkjl
    @Ggdivhjkjl 3 หลายเดือนก่อน +1

    Where do we buy this?

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน +4

      Made my own copy from this pdf: bildsuche.digitale-sammlungen.de/index.html?c=viewer&bandnummer=bsb00082065&pimage=8&v=100&nav=&l=de
      Would be fun to do a reprinting if enough people wanted to buy it.

  • @disgruntledtoons
    @disgruntledtoons 3 หลายเดือนก่อน +1

    The slide rule does the same thing more conveniently, but it didn't change mathematics "forever", either. Looks like an overblown title to me.

  • @zhubajie6940
    @zhubajie6940 3 หลายเดือนก่อน

    As the last generation to use slide rules and tables, you don't understand the power of calculators and computers we now possess although I think hand graphing be it on linear, log, semilog, or polar graph paper and working with other graphical methods (nomographs, families of curves, stability plots, mixture phase, Mollier and other chemical and thermal parameter diagrams and other binary, ternary plots, etc.) gave one an intuition on creating functions to simplify calculations with correlations that can be used in computers.

  • @WideCuriosity
    @WideCuriosity 3 หลายเดือนก่อน

    The circular tool aside, isn't this just a type of logarithmic table ?
    Ah having now got to the end of the video I see this is basically admitted to.

  • @aniksamiurrahman6365
    @aniksamiurrahman6365 3 หลายเดือนก่อน +1

    I'm afraid that, many of such significant work done today will be lost exactly due to the opposite reason. They'll get drowned in millions of publications per year, and get bogged down in impact factor and citation quagmire.

    • @pavelperina7629
      @pavelperina7629 3 หลายเดือนก่อน

      It already is a problem. It's hard to find fundamental in-depth information cause google always returns results which are similar to each other and wiki and basically mainstream. Maybe it's to reduce risk of "misinformation" or low quality information in search results. Imagine that just two weeks ago I had to derive how to extract center of rotation from transformation matrix - i was not able to google it, chatgpt said it's too complex problem. Yes, it needed to multiply three matrices by hand and solve three equations of three unknows having trigonometric functions - but extracting angle was easy so more like two equations without trigs. Another solution was to use some math library and extract eigenvectors. All that google found was the opposite - how to get matrix knowing center of rotation and angle.
      And that was not only problem I had. Sometimes it disregards some search keywords and I was not able to find exact article on my blog. Maybe it filters spam, I don't know. Also it's very hard to find some negative yet informative articles on someones blog - once i could not find that some problem exists, then one guy randomly linked in-depth research about it in youtube video.

  • @saxmusicmail
    @saxmusicmail 3 หลายเดือนก่อน

    Ahhh, looks to be the predecessor to the CRC Mathematical Tables!!!

  • @CheekyLeoGames
    @CheekyLeoGames 3 หลายเดือนก่อน +1

    At 1:51, it doesnt map to 9063 but 90630

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน

      Good eye! Yeah I put a note about this in the description.

  • @thego-o-dstuff1036
    @thego-o-dstuff1036 3 หลายเดือนก่อน +1

    Mathematics IS FOREVER .♾️👍

  • @NotSure416
    @NotSure416 3 หลายเดือนก่อน +4

    honestly, they should teach slide rules in school.

    • @user-lt9nb9dx7t
      @user-lt9nb9dx7t 3 หลายเดือนก่อน +3

      No

    • @NotSure416
      @NotSure416 3 หลายเดือนก่อน

      ​@@user-lt9nb9dx7t haha, why? Learning how to use a slide rule would be awesome.

    • @IsomerSoma
      @IsomerSoma 3 หลายเดือนก่อน +2

      @@NotSure416 It's also completely useless as we have calculators and i also dont see any transferable skill worth of noting. Its also not fun, but tedious.

    • @NotSure416
      @NotSure416 3 หลายเดือนก่อน +2

      @@IsomerSoma Learning sometimes requires a bit of discomfort until one masters a skill. Exponentials and logarithms are extremely useful. Once one learns that basics, then it would be acceptable to use a more powerful tool such as a calculator. We still teach how to add, subtract multiply and divide by hand. Should we not teach long division because it's tedious?

    • @IsomerSoma
      @IsomerSoma 3 หลายเดือนก่อน

      @@NotSure416 Mental arithmetic is useful. I use it daily while doing mathematics (mostly proofs for university; small computations). It would not only be inconvient for me to not know mental arithmetic but also seriously diminish my comprehsion of steps in a proof or to come up with some number trick (like +1 -1 is like adding 0) to transfer some statement into something that has better properties.
      A worse version of a calculator would be completely useless. It gives me no new insight and its just if you are good at it a repetitive, brainless mechanical skill. Afterall that was the entire point of it before it got replaced.
      It isnt tedious because its hard but because its very boring. How the disk caculator is constructed is however quite interesting and ingenious. I still dont think it serves any meaningful purpose if we would still teach this. We would better be served by giving maths a more problem solving direction in school. For computation we not just have calculators ... we can CODE our mathematical algorithms or just download math packages for python. We can do very complex computations this way.
      Being good at numerical analysis as well as being able to put the math into code is WAY more valuable than any calculator or slider skills (there are actually competitions and schools for this especially in asia which is stunningly useless imo). It is also cognitively way more challenging thus generating more transferable learning to other parts in life.
      Tl;dr: It makes no fun, it barely teaches you anything transferable and it is useless in every situation of modern life. The same cant be said about mental arithmetic at all. It is way quicker and more convient to caculate something small in your head than to pull out your smart phone every time. Also being able to do mental arithmetic gives you a basic understanding how operations work which is important to much more abstract and high level mathematics as well as basic every day applications of math in every day life.

  • @fVNzO
    @fVNzO 3 หลายเดือนก่อน +48

    "This 400 year old book"
    Proceeds to manhandle it for 8 minutes and 46 seconds

    • @asdfasdf-dd9lk
      @asdfasdf-dd9lk 3 หลายเดือนก่อน +21

      bro it's obviously a copy ;-; he wouldnt slice up an actual 400 year old book lmao

    • @fVNzO
      @fVNzO 3 หลายเดือนก่อน +1

      @@asdfasdf-dd9lk Off course it's a copy lmao. It was a joke. Myyyy days.

  • @someonespadre
    @someonespadre 3 หลายเดือนก่อน

    Have 1 book of base 10 logarithms and 1 book of logarithmic trig functions, they are fun.

  • @6infinity8
    @6infinity8 3 หลายเดือนก่อน +3

    Logarithms...

  • @mynt4033
    @mynt4033 3 หลายเดือนก่อน

    Am I the only one thrown off by the fact tha the red number in the table doesn't line up with the red number in the written card? 160500 is what I see in the table but what is written is 16096. Is there a missing number place somewhere???

  • @troyfrei2962
    @troyfrei2962 3 หลายเดือนก่อน

    This seems like LOG!

  • @abnormalhorror.
    @abnormalhorror. 3 หลายเดือนก่อน

    at 1:50 its shown that the red number is 9063 , but shouldnt it be 90630? Was just wondering, idk if im wrong xD

    • @WelchLabsVideo
      @WelchLabsVideo  3 หลายเดือนก่อน

      Good eye! I put a note about this in the description.