WEBVTT 99:59:59.999 --> 99:59:59.999 The great texts of the ancient world 99:59:59.999 --> 99:59:59.999 don't survive to us in their original form. 99:59:59.999 --> 99:59:59.999 They survive because Medieval scribes copied them 99:59:59.999 --> 99:59:59.999 and copied them and copied them. 99:59:59.999 --> 99:59:59.999 And so it is which Archimedes, 99:59:59.999 --> 99:59:59.999 the great Greek mathematician. 99:59:59.999 --> 99:59:59.999 Everything we know about Archimedes as a mathematician 99:59:59.999 --> 99:59:59.999 we know about because of just three books, 99:59:59.999 --> 99:59:59.999 and they're called A, B and C. 99:59:59.999 --> 99:59:59.999 And A was lost by an Italian humanist in 1564. 99:59:59.999 --> 99:59:59.999 And B was last heard of in the Pope's Library 99:59:59.999 --> 99:59:59.999 about a hundred miles north of Rome in [unclear] in 1311. 99:59:59.999 --> 99:59:59.999 Now Codex C was only discovered in 1906, 99:59:59.999 --> 99:59:59.999 and it landed on my desk in Baltimore 99:59:59.999 --> 99:59:59.999 on the 19th of January, 1999. 99:59:59.999 --> 99:59:59.999 And this is Codex C here. 99:59:59.999 --> 99:59:59.999 Now Codex C is actually buried in this book. 99:59:59.999 --> 99:59:59.999 It's buried treasure. 99:59:59.999 --> 99:59:59.999 Because this book is actually a prayer book. 99:59:59.999 --> 99:59:59.999 It was finished by a guy called Johannes Myrones 99:59:59.999 --> 99:59:59.999 on the 14th of April, 2029. 99:59:59.999 --> 99:59:59.999 And to make his prayer book he used parchment. 99:59:59.999 --> 99:59:59.999 But he didn't use new parchment, 99:59:59.999 --> 99:59:59.999 he used parchment recycled from earlier manuscripts, 99:59:59.999 --> 99:59:59.999 and there were seven of them. 99:59:59.999 --> 99:59:59.999 And Archimedes Codex C was just one of those seven. 99:59:59.999 --> 99:59:59.999 He took apart the Archimedes manuscript and the other seven manuscripts. 99:59:59.999 --> 99:59:59.999 He erased all of their texts, 99:59:59.999 --> 99:59:59.999 and then he cut the sheets down in the middle, 99:59:59.999 --> 99:59:59.999 he shuffled them up, 99:59:59.999 --> 99:59:59.999 and he rotated them 90 degrees, 99:59:59.999 --> 99:59:59.999 and he wrote prayers on top of these books. 99:59:59.999 --> 99:59:59.999 And essentially these seven manuscripts 99:59:59.999 --> 99:59:59.999 disappeared for 700 years, and we have a prayer book. 99:59:59.999 --> 99:59:59.999 The prayer book was discovered by this guy, 99:59:59.999 --> 99:59:59.999 Johan Ludvig Heiberg, in 1906. 99:59:59.999 --> 99:59:59.999 And with just a magnifying glass, 99:59:59.999 --> 99:59:59.999 he transcribed as much of the text as he could. 99:59:59.999 --> 99:59:59.999 And the thing is that he found two texts in this manuscript 99:59:59.999 --> 99:59:59.999 that were unique texts. 99:59:59.999 --> 99:59:59.999 They weren't an A and B at all; 99:59:59.999 --> 99:59:59.999 they were completely new texts by Archimedes, 99:59:59.999 --> 99:59:59.999 and they were called "The Method" and "The Stomachion." 99:59:59.999 --> 99:59:59.999 And it became a world famous manuscript. 99:59:59.999 --> 99:59:59.999 Now it should be clear by now 99:59:59.999 --> 99:59:59.999 that this book is in bad condition. 99:59:59.999 --> 99:59:59.999 It got in worse condition in the 20th century 99:59:59.999 --> 99:59:59.999 after Heiberg saw it. 99:59:59.999 --> 99:59:59.999 Forgeries were painted over it, 99:59:59.999 --> 99:59:59.999 and it suffered very badly from mold. 99:59:59.999 --> 99:59:59.999 This book is the definition of a write-off. 99:59:59.999 --> 99:59:59.999 It's the sort of book 99:59:59.999 --> 99:59:59.999 that you thought would be in an institution. 99:59:59.999 --> 99:59:59.999 But it's not in an institution, 99:59:59.999 --> 99:59:59.999 it was bought by a private owner in 1998. 99:59:59.999 --> 99:59:59.999 Why did he buy this book? 99:59:59.999 --> 99:59:59.999 Because he wanted to make that which was fragile safe. 99:59:59.999 --> 99:59:59.999 He wanted to make that which was unique ubiquitous. 99:59:59.999 --> 99:59:59.999 He wanted to make that which was expensive free. 99:59:59.999 --> 99:59:59.999 And he wanted to do this as a matter of principle. 99:59:59.999 --> 99:59:59.999 Because not many people are really going to read Archimedes in ancient Greek, 99:59:59.999 --> 99:59:59.999 but they should have the chance to do it. 99:59:59.999 --> 99:59:59.999 So he gathered around himself the friends of Archimedes, 99:59:59.999 --> 99:59:59.999 and he promised to pay for all the work. 99:59:59.999 --> 99:59:59.999 And it was an expensive job, 99:59:59.999 --> 99:59:59.999 but actually it wouldn't be as much as you think 99:59:59.999 --> 99:59:59.999 because these people, they didn't come for money, 99:59:59.999 --> 99:59:59.999 they came for Archimedes. 99:59:59.999 --> 99:59:59.999 And they came from all sorts of different backgrounds. 99:59:59.999 --> 99:59:59.999 They came in from particle physics, 99:59:59.999 --> 99:59:59.999 they came from classical philology, 99:59:59.999 --> 99:59:59.999 they came from book conservation, 99:59:59.999 --> 99:59:59.999 they came from ancient mathematics, 99:59:59.999 --> 99:59:59.999 they came from data management, 99:59:59.999 --> 99:59:59.999 they came from scientific imaging and program management. 99:59:59.999 --> 99:59:59.999 And they got together to work on this manuscript. 99:59:59.999 --> 99:59:59.999 The first problem was a conservation problem. 99:59:59.999 --> 99:59:59.999 And this is the sort of thing that we had to deal with. 99:59:59.999 --> 99:59:59.999 There was glue on the spine of the book. 99:59:59.999 --> 99:59:59.999 And if you look at this photograph carefully, 99:59:59.999 --> 99:59:59.999 the bottom half of this rather brown. 99:59:59.999 --> 99:59:59.999 And that glue is hide glue. 99:59:59.999 --> 99:59:59.999 Now if you're a conservator, 99:59:59.999 --> 99:59:59.999 you can take off this glue reasonably easily. 99:59:59.999 --> 99:59:59.999 The top half is Elmer's wood glue. 99:59:59.999 --> 99:59:59.999 It's polyvinyl acetate emulsion. 99:59:59.999 --> 99:59:59.999 It doesn't dissolve in water once it's dry. 99:59:59.999 --> 99:59:59.999 And it's much tougher than the parchment that it was written on. 99:59:59.999 --> 99:59:59.999 And so before we could start imagining Archimedes, 99:59:59.999 --> 99:59:59.999 we had to take this book apart. 99:59:59.999 --> 99:59:59.999 So it took four years to take it off. 99:59:59.999 --> 99:59:59.999 And this is a rare action shot, ladies and gentlemen. 99:59:59.999 --> 99:59:59.999 (Laughter) 99:59:59.999 --> 99:59:59.999 Another thing is that we had to get rid of all the wax, 99:59:59.999 --> 99:59:59.999 because this was used in the liturgical services 99:59:59.999 --> 99:59:59.999 of the Greek Orthodox Church 99:59:59.999 --> 99:59:59.999 and they'd used candle wax. 99:59:59.999 --> 99:59:59.999 And the candle wax was dirty, 99:59:59.999 --> 99:59:59.999 and we couldn't image through the wax. 99:59:59.999 --> 99:59:59.999 So very carefully we had to mechanically scrape off all the wax. 99:59:59.999 --> 99:59:59.999 It's hard to tell you exactly 99:59:59.999 --> 99:59:59.999 how bad the condition of this book is, 99:59:59.999 --> 99:59:59.999 but it came out in little bits very often. 99:59:59.999 --> 99:59:59.999 And normally in a book, you wouldn't worry about the little bits, 99:59:59.999 --> 99:59:59.999 but these little bits might contain unique Archimedes text. 99:59:59.999 --> 99:59:59.999 So tiny fragments 99:59:59.999 --> 99:59:59.999 we actually managed to put back in the right place. 99:59:59.999 --> 99:59:59.999 Then, having done that, we started to image the manuscript. 99:59:59.999 --> 99:59:59.999 And we imaged the manuscript 99:59:59.999 --> 99:59:59.999 in 14 different wave-bands of light. 99:59:59.999 --> 99:59:59.999 Because if you look at something in different wave-bands of light, 99:59:59.999 --> 99:59:59.999 you see different things. 99:59:59.999 --> 99:59:59.999 And here is an image of a page 99:59:59.999 --> 99:59:59.999 imaged in 14 different wave-bands of light. 99:59:59.999 --> 99:59:59.999 But none of them worked. 99:59:59.999 --> 99:59:59.999 So what we did was we processed the images together, 99:59:59.999 --> 99:59:59.999 and we put two images into one blank screen. 99:59:59.999 --> 99:59:59.999 And here are two different images of the Archimedes manuscript. 99:59:59.999 --> 99:59:59.999 And the image on the left 99:59:59.999 --> 99:59:59.999 is the normal red image. 99:59:59.999 --> 99:59:59.999 And the image on the right is an ultraviolet image. 99:59:59.999 --> 99:59:59.999 And in the image on the right 99:59:59.999 --> 99:59:59.999 you might be able to see some of the Archimedes writing. 99:59:59.999 --> 99:59:59.999 If you merge them together into one digital canvas, 99:59:59.999 --> 99:59:59.999 the parchment is brightened in both images 99:59:59.999 --> 99:59:59.999 and it comes out bright. 99:59:59.999 --> 99:59:59.999 The prayer book is dark in both images 99:59:59.999 --> 99:59:59.999 and it comes our dark. 99:59:59.999 --> 99:59:59.999 The Archimedes text is dark in one image and bright in another. 99:59:59.999 --> 99:59:59.999 And it'll come out dark but red, 99:59:59.999 --> 99:59:59.999 and then you can start to read it rather clearly. 99:59:59.999 --> 99:59:59.999 And that's what it looks like. 99:59:59.999 --> 99:59:59.999 Now that's a before and after image, 99:59:59.999 --> 99:59:59.999 but you don't read the image on the screen like that. 99:59:59.999 --> 99:59:59.999 You zoom in and you zoom in 99:59:59.999 --> 99:59:59.999 and you zoom in and you zoom in, 99:59:59.999 --> 99:59:59.999 and you can just read it now. 99:59:59.999 --> 99:59:59.999 (Applause) 99:59:59.999 --> 99:59:59.999 If you process the same two images in a different way, 99:59:59.999 --> 99:59:59.999 you can actually get rid of the prayer book text. 99:59:59.999 --> 99:59:59.999 And this is terribly important. 99:59:59.999 --> 99:59:59.999 Because the diagrams in the manuscript 99:59:59.999 --> 99:59:59.999 are the unique source for the diagrams 99:59:59.999 --> 99:59:59.999 that Archimedes drew in the sand in the fourth century B.C. 99:59:59.999 --> 99:59:59.999 And there we are, I can give them to you. 99:59:59.999 --> 99:59:59.999 With this kind of imaging -- 99:59:59.999 --> 99:59:59.999 this kind of infrared, ultraviolet, invisible light imaging -- 99:59:59.999 --> 99:59:59.999 we were never going to image through the gold ground forgeries. 99:59:59.999 --> 99:59:59.999 How were we going to to that? 99:59:59.999 --> 99:59:59.999 Well we took the manuscript, 99:59:59.999 --> 99:59:59.999 and we decided to image it in X-ray florescence imaging. 99:59:59.999 --> 99:59:59.999 So an X-ray comes in on the diagram on the left 99:59:59.999 --> 99:59:59.999 and it knocks out an electron from the inner shell of an atom. 99:59:59.999 --> 99:59:59.999 And that electron disappears. 99:59:59.999 --> 99:59:59.999 And as it disappears an electron form a shell farther out 99:59:59.999 --> 99:59:59.999 jumps in and takes its place. 99:59:59.999 --> 99:59:59.999 And when it takes its place, 99:59:59.999 --> 99:59:59.999 it sheds electromagnetic radiation. 99:59:59.999 --> 99:59:59.999 It sheds an X-ray. 99:59:59.999 --> 99:59:59.999 And this X-ray is specific in its wavelength 99:59:59.999 --> 99:59:59.999 to the atom that it hits. 99:59:59.999 --> 99:59:59.999 And what we wanted to get 99:59:59.999 --> 99:59:59.999 was the iron. 99:59:59.999 --> 99:59:59.999 Because the ink was written in iron. 99:59:59.999 --> 99:59:59.999 And if we can map 99:59:59.999 --> 99:59:59.999 where this X-ray that comes out, where it comes from, 99:59:59.999 --> 99:59:59.999 we can map all the iron on the page, 99:59:59.999 --> 99:59:59.999 and theoretically we can read the image. 99:59:59.999 --> 99:59:59.999 The thing is that you need a very powerful light source to do this. 99:59:59.999 --> 99:59:59.999 So we too it to the Stanford Synchrotron Radiation Laboratory 99:59:59.999 --> 99:59:59.999 in California, 99:59:59.999 --> 99:59:59.999 which is a particle accelerator. 99:59:59.999 --> 99:59:59.999 Electrons go around one way, 99:59:59.999 --> 99:59:59.999 positrons go around the other. 99:59:59.999 --> 99:59:59.999 They meet in the middle, 99:59:59.999 --> 99:59:59.999 and they create subatomic particles 99:59:59.999 --> 99:59:59.999 like the [unclear] quark and the [unclear] electron.