00:00:30 Once you get going on a train of thought, you don't need to wait for me to interrupt you.

00:00:41 If you think I'm going too long, don't do that, will you?

00:00:44 Yes, although we can edit, we can go on in a very relaxed manner.

00:00:48 That's the beauty of this amount of video tape, is you've got all sorts of options.

00:00:52 You don't have to change the film every four minutes.

00:00:54 Twenty minutes.

00:00:55 And if we make fools of ourselves, it just can be taken out, which is really very nice about the...

00:01:03 Good.

00:01:05 Five, four, three...

00:01:09 After you left the Navy, you went back to Cambridge and began work on flash photosis very quickly thereafter.

00:01:18 That's right, yes.

00:01:20 I was a chemist and I had decided... I had a lot of time to think in the Navy,

00:01:29 and long hours at sea in the hammock.

00:01:32 And I decided that certainly I wanted to do research.

00:01:39 And I decided the action was on the periphery, to some extent, of chemistry,

00:01:43 on the physics side or on the biological side.

00:01:46 I wasn't quite sure which, still aren't, I think they're both important.

00:01:50 Did you have an idea of the project you were going to do or was it just a general area of research?

00:01:55 No, apart from that, that meant that I decided I wanted to go to the physical chemistry department

00:02:05 or perhaps to the physiology department.

00:02:08 I did in fact nearly do that.

00:02:11 I did have some correspondence with Lord Adrian, as he later became.

00:02:18 But in the event, I went to see Professor Norrish in physical chemistry

00:02:27 and found myself very interested in photochemistry, which was his main field.

00:02:32 I had, of course, heard the name as an undergraduate.

00:02:36 So I decided to do photochemistry and began by throwing myself into the things

00:02:43 which were going on at that time there.

00:02:47 But very quickly you started to develop new techniques, very, very soon into your PhD, in fact.

00:02:55 Yes, well, what happened was that Norrish decided that we needed more intense lamps.

00:03:03 Of course, everybody was using the throwouts from the forces at that time.

00:03:10 His throwout was an enormous army searchlight.

00:03:15 My job was to set this up.

00:03:18 It was a carbon arc source run by an enormous diesel, which was in an army truck.

00:03:28 One of my first jobs was to...

00:03:31 I went in January and cranking this diesel was my first job at 9 o'clock in the morning,

00:03:37 which took half the morning sometimes.

00:03:41 So we had this very bright light source, which turned out really...

00:03:47 What we were going to do was try to look at free radicals directly.

00:03:52 Free radicals were the great thing in reaction kinetics at the time.

00:03:57 And he thought that by having a very intense light source,

00:04:01 we would get a high enough concentration to see them.

00:04:04 Well, that wasn't so, because the lifetime is so short.

00:04:09 And a carbon arc was mainly heat and very little light.

00:04:16 So I replaced that with a 7 kilowatt mercury lamp, which was better.

00:04:25 It was more ultraviolet, but still a continuous source.

00:04:28 And that blew up and I had to go to Siemens Lamp Works in Preston to get another one quickly.

00:04:36 And it was there that I was shown around the factory

00:04:42 and saw the very powerful flash lamps, which they'd been using for aerial photography and so forth.

00:04:49 Now, really, I would have been stupid not to see the connection.

00:04:54 I was looking for free radicals, which lasted for only a thousandth of a second or less.

00:05:02 It's really pointless just to pour continuous lighting to see something for a thousandth of a second.

00:05:09 What you need is a much more intense thing for a thousandth of a second, and that's just what the flash was.

00:05:14 And so, having nothing else to do after I'd been to the factory,

00:05:20 what else can you do in the station hotel in Preston?

00:05:26 I sat down and thought this out in some detail, and when I went back the following day,

00:05:32 I put a proposal to Norrish that this is what I wanted to drop my searchlight

00:05:38 and the cranking of the diesel and try the flash lamps,

00:05:41 which he accepted immediately as being a very good thing to try.

00:05:47 But I also read that you got some lamps from the Navy.

00:05:51 In fact, someone said that you were paid to take them away almost.

00:05:54 Well, not the lamps, but the way you powered the lamps, of course,

00:06:02 was with a big bank of capacitors, condensers.

00:06:06 And I thought it was going to be more difficult than it was,

00:06:12 and so I built a very big apparatus with a lot of power, a lot of condensers.

00:06:17 And it was those that I got from the Navy, yes.

00:06:21 I'd only been out of the Navy a year or so, and I rang my friends and said,

00:06:26 I knew they had any of these condensers, and they said,

00:06:29 oh yes, we've got fields full of them.

00:06:32 And they sent them to me in a very motley collection they were,

00:06:36 and they went on sending them.

00:06:39 They came in lorry loads, they filled the whole department practically.

00:06:47 In fact, I had to get a separate lab to put them in.

00:06:51 And we wired them all up.

00:06:54 And some of them were done, and we got 999.

00:06:59 I had about a thousand.

00:07:00 We got 999 condensers discharging through the other one,

00:07:04 which splattered tar all over the room.

00:07:06 So it was quite an exciting time.

00:07:09 But that's where I got those free.

00:07:12 In fact, I got them more than free.

00:07:15 They gave me five shillings back on each crate,

00:07:19 so I had a little profit out of the transaction.

00:07:22 So you had your light source.

00:07:24 That was one problem.

00:07:26 But you also had to find a way of measuring these reactions.

00:07:29 Was that a problem too?

00:07:30 It was a very big one.

00:07:32 I wasted, really, I suppose, I wasted a lot of time.

00:07:37 Certainly, it wasn't entirely a waste.

00:07:40 All right, I had the flash,

00:07:42 and eventually got that working with these condensers and so forth.

00:07:46 And then how do you measure it?

00:07:48 And thinking of radar,

00:07:53 I thought of an electronic method of doing it

00:08:00 with a scanning spectrograph.

00:08:07 And I built, I tried to build,

00:08:09 I did build a scanning spectrograph,

00:08:11 that is to say I had a grating spectrograph

00:08:13 with a rotating mirror in it

00:08:15 which scanned the spectrum sort of continuously

00:08:19 so that I tried to get the whole spectrum after the flash.

00:08:25 And that wasn't the way to do it,

00:08:27 though it just wasn't the time resolution of a scanning,

00:08:30 nor was the intensity to do it.

00:08:33 I was trying to get too much information.

00:08:35 I was trying to do, with one flash,

00:08:37 I was then trying to whiz around,

00:08:40 whiz through the whole spectrum with the mirror

00:08:42 and get the whole spectrum.

00:08:45 And that meant moving very quickly and very poor resolution.

00:08:48 And it was a difficult thing to build,

00:08:52 and it wasn't a very, it worked,

00:08:54 it wasn't a very successful instrument.

00:08:56 We were the first scanning spectroscopes,

00:08:58 but it wasn't a very successful instrument.

00:09:01 And then, in using the flash,

00:09:06 I was getting, in any case, by scattered light,

00:09:09 I was getting beautiful continuous spectra,

00:09:11 and I suddenly thought, well, that's what I need, really.

00:09:15 And I then had, which really the second part of the idea

00:09:21 came in two parts.

00:09:22 And the second, very successful one,

00:09:24 was to use a second flash,

00:09:27 just the same as the first but weaker,

00:09:30 and delayed.

00:09:31 I did the delay by a spinning wheel,

00:09:33 which, with contacts on it,

00:09:36 an idea which had come from an American radar set,

00:09:40 which, instead of using electronic bows,

00:09:42 used a spinning wheel.

00:09:44 It was called the SL.

00:09:45 And I used that.

00:09:47 So I had two contacts on the spinning wheel.

00:09:49 The first contact fired the big flash,

00:09:51 which produced the radicals.

00:09:53 And then, as the wheel turned round,

00:09:55 the second contact fired the second flash.

00:09:59 And that was that.

00:10:00 And I got the whole spectrum,

00:10:02 say, a thousandth of a second later.

00:10:04 And then I moved the second contact

00:10:07 slightly round the wheel to two milliseconds,

00:10:09 two thousandths of a second,

00:10:11 and got the second whole spectrum and so on.

00:10:14 That was very much better information theory

00:10:17 because I was, again, using a flash.

00:10:21 Instead of trying to use a continuous light,

00:10:23 I was using a flash for the second recording

00:10:27 part of the experiment as well.

00:10:29 And that worked.

00:10:31 So once you overcame the technical problems

00:10:34 of the equipment,

00:10:36 your first molecule that you studied was what?

00:10:42 The first molecule...

00:10:44 Actually, the problem that Norrish had set me

00:10:49 right at the beginning,

00:10:51 and I didn't mention this,

00:10:53 the first thing I did was...

00:10:55 The first technique I used

00:10:57 was a thing called the Panet mirror technique

00:10:59 where you flow...

00:11:00 It was a flow system.

00:11:02 And you flowed...

00:11:04 Having put the searchlight onto your gas,

00:11:06 you flowed the gas along a tube.

00:11:09 And at various distances,

00:11:10 you put little metal mirrors

00:11:13 and the free radicals removed those mirrors.

00:11:15 It works, but it's subject to poisoning,

00:11:19 it's very inaccurate, and so on.

00:11:23 So that...

00:11:25 I had already been using that.

00:11:28 But then, when I got the double flash,

00:11:33 you say, what was the first thing I looked at?

00:11:35 The first thing I looked at

00:11:36 was the molecule I had been looking at

00:11:39 by this Panet mirror method,

00:11:41 which was methylene.

00:11:43 Methylene is CH2,

00:11:46 and you get that from ketene, CH2CO.

00:11:51 And another one I'd been looking at was acetone

00:11:54 to try and get the methyl radical.

00:11:56 Well, the very first material,

00:11:58 when everything was working,

00:11:59 the very first material I put into the tube

00:12:01 was acetone.

00:12:03 And...

00:12:05 I let off the flash.

00:12:08 And my main fear was that nothing would happen,

00:12:10 the flash just wouldn't be big enough

00:12:12 or anything like that.

00:12:14 Well, when I removed the lid of the flash tube,

00:12:19 the tube, it was a meter-long tube,

00:12:22 which had had acetone in it,

00:12:24 had black cobwebs right through it.

00:12:26 The acetone had completely decomposed into carbon.

00:12:30 And these black cobwebs were cobwebs of carbon.

00:12:33 Well, that wasn't what I wanted,

00:12:34 but it was beyond what I...

00:12:36 It was obviously too powerful,

00:12:38 I got too much, and that was great.

00:12:40 I knew that at least I had the power now

00:12:44 to go ahead with this and reduce...

00:12:47 And so I reduced the energy and looked for methyl radical,

00:12:49 which I didn't find,

00:12:51 because it's in the ultraviolet region,

00:12:54 which my spectrograph didn't quite cover.

00:12:56 Very near to it, actually, but not quite.

00:13:01 The first really exciting radical that I got

00:13:09 was CLO.

00:13:17 Fred Dainton, Professor Dainton,

00:13:19 Dr. Dainton as he then was,

00:13:21 was looking at the carbon monoxide chlorine reaction.

00:13:25 And I thought I would look at that

00:13:28 and look for the COCL radical.

00:13:31 I didn't get the COCL radical, but there were changes.

00:13:35 But when I had some oxygen in it as well,

00:13:39 I got a beautiful new spectrum.

00:13:41 And then when I took the carbon monoxide out,

00:13:44 I still got the beautiful new spectrum.

00:13:46 So I was getting it from just chlorine and oxygen.

00:13:49 And it was fairly obviously a diatomic molecule.

00:13:53 Well, if you have chlorine and oxygen and it's diatomic,

00:13:56 you don't have a lot of choice.

00:13:58 You don't have a lot of options.

00:14:00 And it was in fact CLO, which hadn't been observed before.

00:14:03 So was this very exciting?

00:14:05 It was very exciting because it's a beautiful spectrum.

00:14:07 I was able to do it.

00:14:09 It lasted about five milliseconds,

00:14:11 which in those days was a nice long time for my apparatus.

00:14:16 My apparatus was only good for about a millisecond.

00:14:19 So I had plenty of time to study it.

00:14:22 And I was able to do some good kinetics on it.

00:14:26 It disappeared by two CLO molecules coming together.

00:14:29 The whole thing reverses.

00:14:31 That's another nice thing about it.

00:14:33 You could go on with the same mixture.

00:14:36 It was a totally reversible reaction.

00:14:38 After less than a second, it was back where it started.

00:14:42 So you could go on using the same mixture all the time.

00:14:44 Very economical.

00:14:45 Very economical.

00:14:47 But it was really very exciting to take...

00:14:50 I took... These were ten-inch plates in the spectrograph

00:14:53 to take this ten-inch plate into the dark room

00:14:56 and under the red light see this beautiful series of bands coming up

00:15:01 and disappearing in about five milliseconds and so on.

00:15:04 So I spent quite a bit of time on that

00:15:06 analyzing the spectrum, which told us a lot about the CLO,

00:15:10 and then looking at the kinetics of the decay.

00:15:16 And it was very nice.

00:15:18 It produced some nice fundamental results.

00:15:22 Absolutely useless, of course.

00:15:25 So it appeared.

00:15:27 In fact, I remember...

00:15:30 ...Norrish bringing around some industrial people to look at this

00:15:36 and they said, well, what use is this?

00:15:40 In those days, I was very young, and I said what I don't say nowadays.

00:15:45 I said, oh, absolutely no use at all.

00:15:47 It's basic science.

00:15:51 I couldn't really see any application of it,

00:15:54 except, of course, to know about it

00:15:58 as part of the structural chemistry.

00:16:02 But the funny thing is, the way it's turned out,

00:16:07 you never know, do you?

00:16:11 The hole of the Antarctic, the ozone hole, is due to CLO.

00:16:18 There it is, destroying the ozone over the Antarctic and in other parts.

00:16:24 The CLO radical plays the part of the NO radical.

00:16:28 NO does the same thing.

00:16:30 And, of course, it's made from the chlorine

00:16:32 which comes from the chlorofluorocarbons,

00:16:35 from aerosol sprays and so forth.

00:16:38 So immediately this danger was perceived

00:16:42 of the chlorofluorocarbons making chlorine in the stratosphere

00:16:46 and destroying the ozone there.

00:16:48 Immediately that was perceived.

00:16:50 Information was needed about the CLO radical,

00:16:54 which is the heart of the matter,

00:16:56 and it was all there, 30 years later.

00:16:59 It's wonderful, isn't it?

00:17:01 After you had done this,

00:17:03 did you know immediately that this technique

00:17:06 was really going to be very, very important?

00:17:09 Did you know it right away,

00:17:11 or was it just over a period of years

00:17:13 that you realized how important this technique was going to be?

00:17:16 A bit of both, but really the first.

00:17:20 When I first thought of it,

00:17:23 of the flash and then the double flash,

00:17:26 I was really very excited.

00:17:28 I couldn't wait to get back to Cambridge

00:17:30 and propose to do this.

00:17:32 It seemed to me the answer.

00:17:33 But I've had other ideas since then

00:17:36 which I was almost as excited about

00:17:38 which haven't turned out to be so successful.

00:17:43 But when I did eventually,

00:17:46 a year later now because of the time I wasted

00:17:48 with the first method,

00:17:50 when I did eventually see that CLO

00:17:52 and a number of others as well,

00:17:54 of course, coming quickly afterwards,

00:17:56 yes, I realized that it was going to be

00:18:00 a very powerful method for free radical chemistry.

00:18:05 What I didn't realize, perhaps,

00:18:07 is how it would develop in two ways.

00:18:13 Firstly, that it would be extended to many things

00:18:16 apart from free radicals,

00:18:17 almost anything produced by light

00:18:20 which lives for a short time.

00:18:22 But secondly, I didn't know

00:18:28 that the laser was going to be invented

00:18:31 and that the flashes would become,

00:18:34 instead of milliseconds and microseconds,

00:18:37 would become nanoseconds and picoseconds

00:18:39 and femtoseconds.

00:18:40 And that's been the exciting thing since, of course,

00:18:43 that it's been possible to get shorter and shorter

00:18:46 and more and more powerful flashes.

00:18:48 And so the whole pulse and probe technique

00:18:52 is what it is, really,

00:18:54 or the double flash technique

00:18:57 is what is used now in all these regions with lasers.

00:19:02 You were in Cambridge from 1947 to 1957.

00:19:07 Pretty well, yes.

00:19:11 Not quite 57, 55.

00:19:13 Oh, excuse me.

00:19:14 1947 to 1955.

00:19:16 What else did you do?

00:19:18 I mean, this was a fair period of time.

00:19:21 Were there any other things that you worked on

00:19:23 that were significant in that period?

00:19:25 It was January 46 to 55.

00:19:30 January 46 to 55.

00:19:32 It was nine years, yes.

00:19:34 Sorry, you were saying?

00:19:35 What else after the chlorine and oxygen molecule?

00:19:39 What did you move on to after that?

00:19:41 Well, a lot of other free radicals,

00:19:45 diatomics and so on.

00:19:49 But the next big step,

00:19:52 it's rather an interesting story,

00:19:54 which is worth telling, I think.

00:19:58 A man called Mr. John Wilson came to see me.

00:20:04 Marvellous man, great enthusiast,

00:20:07 who was director of the British Rayon Research Association.

00:20:11 And he was always enthusiastic about everything

00:20:17 and he was very enthusiastic when he was shown my apparatus and so forth.

00:20:22 And said, oh, well, we must make some use of this.

00:20:26 Now, we have a problem.

00:20:28 Our curtains fall to bits in the sunlight.

00:20:33 Now, at that time I was working on diatomic free radicals in the gas phase

00:20:37 and the idea of curtains was a long way from my future projections.

00:20:46 But he insisted, he was a great enthusiast.

00:20:52 And what is more, he offered to build a second apparatus

00:20:57 and pay a student to do it,

00:21:00 if I would look at his problem of what is called the phototendering of fabrics.

00:21:08 And so I thought a bit about this.

00:21:13 And it so happened that at that time

00:21:19 the triplet state of molecules was being looked at

00:21:26 by phosphorescence and in glasses and so on.

00:21:31 And it occurred to me that in the first place

00:21:35 we might look at some of the dye stuffs,

00:21:38 they were anthraquinone dye stuffs, most of them,

00:21:41 and see what the first step was

00:21:43 and whether we could actually see the triplet state in solution.

00:21:46 The triplet state had never been seen in absorption,

00:21:49 in solution or in the gas phase, of any molecule at all.

00:21:54 Sorry, should we go on to the next class?

00:21:57 No, I couldn't believe it.

00:22:12 So we were looking at these dye stuffs and the fabrics.

00:22:18 What was the actual last sentence?

00:22:20 Well, it doesn't matter if we repeat it because...

00:22:27 Anthraquinone, the triplet state.

00:22:30 I think I know what I was just going to say.

00:22:32 I was in fact just going to say, and it worked.

00:22:36 But it's OK to start the idea again because we just cut out a bit of the...

00:22:41 I'm not taking none of the words.

00:22:43 No, just to tell us where we are in tape one and tape two.

00:22:51 Great.

00:22:53 Just pick it up where you were.

00:22:56 The student was called Morris Windsor

00:23:00 and he quickly built this apparatus and put in some, not dyes,

00:23:06 in the first place we put in naphthalene and anthracene

00:23:10 and it worked like a dream.

00:23:12 We got the sort of sequence which I'd had with the free radicals

00:23:16 but now it was the triplet state absorption for sure of these.

00:23:21 And we put in dozens, hundreds eventually, of molecules

00:23:25 and got triplet states of nearly all of them.

00:23:28 And of course the triplet state has a long lifetime.

00:23:32 It's the metastable state.

00:23:34 It's the first state which is...

00:23:37 When you excite a molecule you first of all go to the upper singlet state

00:23:42 and that has typically a lifetime of only a billionth of a second,

00:23:45 a few billionths of a second,

00:23:47 and that was way beyond us in those days although we've seen them since.

00:23:51 But it then crosses over to this metastable triplet state

00:23:55 which has two advantages in the first place.

00:23:58 I can see it because it lasts for milliseconds

00:24:02 and secondly because it lasts so long

00:24:05 it is photochemically very important and it has time to react.

00:24:09 And we saw it.

00:24:11 And it is in fact the excited state of molecules

00:24:19 which does cause the phototendrons.

00:24:22 Whereas I had had my tongue in my cheek when I started looking,

00:24:25 I thought it would be nice to look at the triplets

00:24:27 but I don't think I'm going to look at curtains.

00:24:29 It was in fact right on the ball,

00:24:32 right on the beam for solving that problem.

00:24:35 And we then did look at anthraquinone itself and other quinones and dyes

00:24:40 and sure enough we were able to see not only the triplet state

00:24:44 but we were able to see the triplet state attacking the curtains.

00:24:49 Actually we didn't have curtains.

00:24:51 We put it in alcohol solution and so on.

00:24:53 It's just the same.

00:24:55 It goes for cellulose just as it goes for alcohol.

00:24:58 And the free radicals which are then formed.

00:25:01 And then you could watch the disappearance of the radicals.

00:25:03 You could watch them react with oxygen.

00:25:05 And so it was all there.

00:25:08 I did this with Keith Bridge

00:25:11 and we were able to see the whole sequence

00:25:14 with the excited state and the free radicals

00:25:18 which follow the absorption of sunlight by those dyestuffs.

00:25:22 And understand there were some very peculiar, very interesting things about it.

00:25:27 Some dyestuffs in light just tore the curtains to bits.

00:25:34 And some very similar ones.

00:25:36 Just groups in slightly different positions didn't.

00:25:40 And there seemed to be no sense in this.

00:25:42 It was very difficult to find out why.

00:25:44 But we were able to sort that out.

00:25:47 It was that the groups themselves were attacked by reactions within the molecules

00:25:53 rather than attacking the curtains or the alcohol.

00:25:58 That was one reason.

00:26:00 Another reason was the groups switched around the exact position,

00:26:07 the exact energy of the triplet states.

00:26:09 There are more than one triplet state.

00:26:12 Some are called n-pi and some are called pi-pi triplet states.

00:26:18 The n-pi states are active and pull hydrogen from the fabric.

00:26:25 The pi-pi states don't.

00:26:27 As you put in groups to these molecules, you switch them around.

00:26:30 It's the bottom one that matters.

00:26:32 So if you reverse those states, you change a molecule from being active to being inactive.

00:26:37 So all this was eventually sorted out.

00:26:40 And that was the beginning of...

00:26:42 Those were very big molecules to me at the time,

00:26:45 having come from CLO and HS and OH and things like that.

00:26:51 And I suppose they managed to get rid of a bit of my fright

00:26:58 at being confronted with a molecule with more than three or four atoms.

00:27:03 And I've really gone to bigger and bigger ones

00:27:08 until now I'm looking at big biological molecules and so forth.

00:27:13 Well, you're looking at chlorophyll, yes.

00:27:16 Yes.

00:27:17 And photosynthesis, actually, which is even faster than you started out.

00:27:22 Yes.

00:27:24 It is the singlet state that matters.

00:27:28 And that only lasts for...

00:27:32 Well, the longest is about six nanoseconds.

00:27:39 But, of course, when it's in the plant, it's even less than that.

00:27:44 Three or four hundred picoseconds at the most.

00:27:47 Well, that was totally impossible until we developed the laser techniques.

00:27:54 The laser was invented in 1960.

00:27:58 We got a laser fairly early on, but it was hard to compete in the UK

00:28:04 because they had...

00:28:05 You know, Bell Labs were...

00:28:08 And one or two others in the States were already making lasers

00:28:12 when we couldn't get them here.

00:28:13 So it was quite difficult to compete.

00:28:17 But eventually, before I moved to the Royal Institution,

00:28:22 we had lasers working.

00:28:23 We did some...

00:28:27 I think one of the first photochemical experiments with lasers.

00:28:31 Jeff Steinfeld in Sheffield did this with me.

00:28:35 And then incorporating lasers into a flash photolysis apparatus

00:28:40 I did as soon as I got to the Royal Institution.

00:28:44 Was there anything else that you did in the period at Cambridge

00:28:47 which was significant?

00:28:49 Or was it just building on the early work?

00:28:51 No.

00:28:52 There was...

00:28:53 I mean, yes.

00:28:54 There was one other totally different field, yes,

00:28:58 which pleased me very much at the time.

00:29:07 G. N. Lewis had done some work at the beginning,

00:29:12 early years of the war.

00:29:15 He died shortly afterwards,

00:29:18 on frozen glasses, organic glasses,

00:29:24 at liquid nitrogen temperature.

00:29:27 And it occurred to me...

00:29:29 In fact, Lewis had, as I discovered later,

00:29:34 done some rather similar experiments on much more stable radicals

00:29:38 to the ones I was proposing.

00:29:40 But it occurred to me,

00:29:42 why don't I put one of these molecules

00:29:49 which produces a free radical,

00:29:52 like acetone or chlorine dioxide,

00:29:57 to get the CLO,

00:29:59 which in fact is the first one I did,

00:30:02 into a frozen glass at liquid nitrogen temperature

00:30:05 and irradiate it

00:30:07 and hope that it will be broken up.

00:30:09 But then the bits that fly off

00:30:11 will be frozen in separately in the glass

00:30:13 and it'll be there forever.

00:30:16 And would it be there forever?

00:30:18 Well, you think.

00:30:20 Look at a stained glass window.

00:30:22 A stained glass window has these pigments in it,

00:30:25 molecules quite close together,

00:30:28 and yet over thousands of years

00:30:30 they don't diffuse and merge.

00:30:33 So why not?

00:30:35 And an American postdoc

00:30:39 came to work with me for a year,

00:30:41 Erwin Norman,

00:30:43 and I suggested that he might try this.

00:30:47 And after breaking a lot of courts' duels

00:30:50 and this sort of thing,

00:30:52 we got that to work as well.

00:30:54 This was all about the time

00:30:55 the triplet state was coming along.

00:30:57 It was a very exciting time

00:30:59 with the flash of doses.

00:31:01 And sure enough, he put ClO2 in

00:31:04 and we got the ClO radical.

00:31:06 They're forever now.

00:31:09 We called it trapped radicals in glasses.

00:31:13 A letter to nature, trapped radicals in glasses.

00:31:16 And it became quite a big thing.

00:31:19 There were other approaches to it

00:31:21 which followed very closely afterwards,

00:31:24 quite independently.

00:31:25 Herb Breuder was one who,

00:31:28 they called it matrix isolation.

00:31:31 They passed the material along a hot tube

00:31:35 and then trapped the radicals

00:31:38 on a cold finger.

00:31:42 Whereas I was doing it in situ

00:31:44 by shining light on them.

00:31:46 In fact, there was a great excitement

00:31:50 around that time

00:31:51 because they were going to use them as rocket fuels.

00:31:53 They thought if they could freeze enough radicals,

00:31:55 there's a lot of stored power there

00:31:56 and they could use them as rocket fuels.

00:31:58 That never turned out to be important.

00:32:00 But it is a much-used technique to this day.

00:32:04 It's a way of looking at unstable molecules

00:32:07 by producing them by light or other methods,

00:32:11 isolating them in matrices

00:32:13 and keeping them for a long, long time

00:32:15 so that you don't have to use flash methods quickly,

00:32:20 which are always difficult, of course,

00:32:22 if you have a long time to look at something,

00:32:24 you can do it with greater precision.

00:32:27 One of the areas of free radicals

00:32:32 which turned out to be particularly successful and interesting

00:32:36 were the aromatic radicals,

00:32:40 those based on benzene.

00:32:44 Toluene gave us the phenyl radical.

00:32:47 I'm sorry, Toluene gave us the benzyl radical

00:32:49 in flash photolysis.

00:32:51 So we immediately put this now into the trapped radical,

00:32:55 cold, trapped radical apparatus

00:32:57 and got the benzyl radical.

00:32:59 That was so easy that we then began to run through

00:33:02 the whole of organic chemistry

00:33:04 and we detected dozens and dozens of these radicals,

00:33:08 all for the first time,

00:33:09 quite interesting spectroscopically.

00:33:12 In fact, we published a lot on those

00:33:16 and not much has been done about it since.

00:33:21 There they are, there are some papers there sitting away

00:33:23 with hosts, tons of information about...

00:33:26 For example, one we were excited about

00:33:28 that I was trying to get for a long time,

00:33:30 we eventually did get in Sheffield,

00:33:32 was the phenyl radical.

00:33:36 That's benzene with just one hydrogen atom of it.

00:33:39 And we studied that in some detail,

00:33:42 all the spectra are known,

00:33:44 but I haven't looked at the very recent literature,

00:33:49 but I'm not aware that anyone has followed this up at all.

00:33:52 So that really did turn out so far to be quite useless research,

00:33:56 but one day I'm sure it will be useful.

00:34:01 In Sheffield, you of course gathered

00:34:04 quite a large group of people around you,

00:34:06 you were diversifying obviously.

00:34:09 Can you tell me a little bit more

00:34:11 about what was going on in Sheffield?

00:34:14 Well, it was...

00:34:17 The triplet state work that I mentioned

00:34:20 was only just begun,

00:34:23 we'd hardly begun it in Cambridge,

00:34:25 we'd shown that it worked and then we moved to Sheffield.

00:34:28 And nearly all the triplet state work,

00:34:30 there's an enormous amount of...

00:34:34 I mean, the triplet state is

00:34:37 a whole major area of photochemistry and even chemistry,

00:34:42 and so there were all sorts of aspects of that,

00:34:46 how it disappeared,

00:34:48 radiation-less processes of jumping from one state to another,

00:34:56 quenching, exit on...

00:35:01 annihilation between two excited states and so forth,

00:35:05 all these things were studied in that time in Sheffield.

00:35:09 As I said, I began...

00:35:12 We built our first laser apparatus there,

00:35:16 which then developed when I got to the Royal Institution.

00:35:22 And I began my interest in photosynthesis there.

00:35:26 We began to look at...

00:35:28 to do flash photosythesis under the microscope

00:35:31 on single cells of chloroplasts of the green leaf,

00:35:36 which I continued to do ever since.

00:35:38 You were still working in the lab in Sheffield, were you?

00:35:41 Yes.

00:35:43 I had a lot, like all professors, heads of department,

00:35:47 I had a lot of other things to do, administration of the department,

00:35:51 and quite a lot of committee work in London was building up by then.

00:35:56 But certainly I was in the lab every day,

00:36:01 I did less and less with my own hands,

00:36:03 simply because my own hands were not as good as those of my students.

00:36:07 Did you miss that?

00:36:09 Yes, yes.

00:36:11 I think one misses it mainly

00:36:14 because you really get your original ideas,

00:36:18 your really new ideas, whilst you're doing it somehow.

00:36:22 If you're doing routine, doing an experiment routine,

00:36:27 you see every little detail of it,

00:36:30 and you see what the snags are,

00:36:32 and it's there that you have the idea of doing something differently.

00:36:37 Whereas if you're suggesting the ideas to other people

00:36:42 and then they tell you what happened,

00:36:44 you'll miss that intermediate stage.

00:36:47 And the fun, as I mentioned,

00:36:50 the developing of that plate and seeing it come up,

00:36:53 really exciting indeed.

00:36:55 The excitement is a little second-hand

00:36:57 when you get it from the student,

00:37:02 even if it tells you right away.

00:37:05 And of course the trouble is

00:37:09 that when a student gets an exciting result,

00:37:11 he's so keen to get on with it

00:37:14 that he doesn't always come and tell you.

00:37:17 A student can be guaranteed to come and tell you

00:37:20 if everything's going wrong,

00:37:22 but not always if everything's going right.

00:37:25 You had some very good people working with you in Sheffield too.

00:37:28 I did, yes.

00:37:29 The universities, in England at least,

00:37:32 are populated with former students of yours,

00:37:34 or former students and members of staff.

00:37:37 Yes, and members of staff.

00:37:39 We had a very good staff there.

00:37:41 It was a really marvellous, lively department

00:37:44 in the late 50s and 60s, yes, it was.

00:37:49 I think I last counted there were 26 professors

00:37:54 from there in other universities, yes.

00:37:58 But you must have also had time for some other things than science

00:38:02 while you were both in Cambridge and in Sheffield.

00:38:05 Did you have any leisure activities that you pursued?

00:38:09 Yes, we did a lot of travelling,

00:38:12 almost always to scientific conferences,

00:38:14 but we made a holiday of it as well.

00:38:18 I used to play a bit of tennis.

00:38:21 We used to go skiing every winter.

00:38:24 We always had a skiing holiday.

00:38:27 And I did a bit of sailing, dinghy sailing in those days.

00:38:31 I mean, Sheffield isn't the best place for sea sailing,

00:38:36 but I had a dinghy and I used to sail with some of my friends there

00:38:42 like John Murrell and Richard Dixon, who are professors now.

00:38:47 Were you sorry to leave Sheffield?

00:38:50 I mean, did you have any ambivalence about leaving Sheffield to come to the RI?

00:38:54 Not really, no.

00:38:56 I mean, I liked Sheffield, not to say I didn't like Sheffield,

00:38:58 but I'd been there 11 years.

00:39:00 I was the head of the chemistry department.

00:39:02 I didn't want to be a dean,

00:39:04 which I was just about going to be if I'd stayed there.

00:39:08 I didn't want to be a vice-chancellor anywhere else and so forth.

00:39:13 So that really the only thing to do

00:39:18 would be to move to another chair of chemistry in another university

00:39:22 or to the Royal Institution,

00:39:25 which was very much on my mind

00:39:29 because I'd given some lectures there

00:39:32 and I was a professor there in the sense that it was a sort of honoury.

00:39:36 Well, it was an honoury in the sense that I was paid for the hard lecture that I gave.

00:39:41 And I gave a couple of discourses and some schools lectures

00:39:45 and I got very excited.

00:39:47 It was a marvellous place. I got very excited about that.

00:39:51 By this time I was really enjoying lecturing

00:39:55 and quite enjoying popular lectures.

00:40:01 And in fact, during the last two years I was at Sheffield,

00:40:07 I did a very extensive television series called The Laws of Disorder,

00:40:14 which was very successful.

00:40:17 It was shown four times on BBC television.

00:40:23 This was in the days of black and white and only one channel,

00:40:28 so everybody had to watch it, you see, because they had no choice.

00:40:32 So everybody saw this.

00:40:34 It must have been, of all the scientific lectures I've given,

00:40:37 I suppose it got the biggest audience of the lot.

00:40:40 And I enjoyed this so much.

00:40:42 I didn't do that at the Royal Institution,

00:40:45 but the Royal Institution was obviously a place

00:40:48 where people like Faraday and people that no one could possibly live up to

00:40:54 had managed to do popular lectures and so forth,

00:40:58 and pretty good research.

00:41:01 So I thought this would be something exciting and I would try it

00:41:06 when I was offered the job.

00:41:08 How did you come to make the television series?

00:41:12 Did someone approach you? Was it your idea?

00:41:15 How did this come about?

00:41:17 It's quite an extraordinary subject for a television series.

00:41:21 Like everything else, one thing grows out of another.

00:41:25 The sequence is very simple.

00:41:28 I had to give, like everybody else, an inaugural lecture

00:41:31 at the Royal Institution.

00:41:33 Sorry, an inaugural lecture at Sheffield,

00:41:35 and I became a professor there.

00:41:37 There were so many professors being appointed

00:41:39 that my inaugural lecture was given after I'd been there about seven years.

00:41:44 And the Vice-Chancellor, Dr. Whittaker, said,

00:41:50 Now, let's have something exciting.

00:41:53 Let's have lots of demonstrations.

00:41:56 I said, I don't know that I can really do demonstrations.

00:41:59 Physical chemistry, you know, thermodynamics, it's very difficult.

00:42:04 And he said, You can. I've seen it, and they're very good.

00:42:07 Let's have some battles and things.

00:42:09 He was a mathematician and a very academic person,

00:42:11 but he wanted this, and I thought,

00:42:13 Well, if the Vice-Chancellor wants it, I'll try it.

00:42:15 So I put a lot of effort into it,

00:42:17 and I did a rather spectacular inaugural lecture,

00:42:25 which I was immediately asked to give again at various places and so on.

00:42:28 But particularly, one of the Sheffield people told Sir Lawrence Bragg about it,

00:42:35 and he invited me to give a discourse at the Royal Institution.

00:42:39 I hadn't lectured at the Royal Institution,

00:42:42 and I gave more or less this inaugural lecture as the discourse.

00:42:47 And they liked it, and Sir Lawrence asked me

00:42:52 whether I would be a professor at the Royal Institution,

00:42:54 so I did a number.

00:42:56 And about two years later, it was my turn to give a discourse again.

00:43:02 We don't give those too often.

00:43:04 And I got together one on thermodynamics,

00:43:08 which sounds the most unpromising subject for a popular lecture,

00:43:11 and I called it the laws of disorder.

00:43:14 And, of course, a lot of people go from all over the place,

00:43:19 go to these lectures,

00:43:21 and among the audience was a person called Philip Daly in the BBC,

00:43:28 who I was a great admirer of, or I have been.

00:43:33 He died recently.

00:43:35 He was a pioneer of science on television,

00:43:38 and he asked me would I consider doing a whole series on this.

00:43:41 I had done one program before.

00:43:43 That wasn't my first.

00:43:44 I did one.

00:43:45 There was a series on BBC television in those days called Eye on Research.

00:43:52 And they came to Sheffield and did one on the...

00:43:58 It was called Quick as a Flash, on my research.

00:44:02 And Philip Daly was...

00:44:04 It's like a lot of 20 minutes.

00:44:16 Philip Daly and...

00:44:19 Albus Singer, Philip Daly, Raymond Baxter.

00:44:23 Yes.

00:44:24 They were all there. Yes.

00:44:26 Albus Singer, I know.

00:44:28 Are we ready to go?

00:44:29 OK.

00:44:30 So, Quick as a Flash was the first thing you'd actually appeared in.

00:44:35 That's right.

00:44:36 That's right.

00:44:37 And pretty well the science team at the BBC

00:44:41 came up to Sheffield and did a series on it.

00:44:44 The BBC came up to Sheffield to do that.

00:44:46 That was Albus Singer and Raymond Baxter presented it.

00:44:53 But Philip Daly in particular.

00:44:55 And so I knew them.

00:44:58 And when I went down to the Royal Institution, they knew me.

00:45:01 And they thought this was, of all subjects,

00:45:05 thermodynamics for ten lectures on television would be a good thing.

00:45:11 So I agreed to do it.

00:45:12 And I put a lot of effort into that.

00:45:14 As a matter of fact, it wasn't just lecturing on what I knew.

00:45:20 I tried to think out new approaches to some parts of thermodynamics

00:45:26 which would be understood by the non-scientists.

00:45:32 I had a lot of demonstrations,

00:45:34 but I particularly approached thermodynamics

00:45:37 as well as the title The Laws of Disorder implies,

00:45:41 as through entropy being a mixed-upness, a chaos,

00:45:46 and how to measure that,

00:45:48 with examples from things that people are familiar with

00:45:52 like games of cards and dice and that sort of thing.

00:45:59 And so that's how it happened.

00:46:04 But ten lectures is a lot of material.

00:46:06 Weren't you ever overwhelmed by what you'd undertaken?

00:46:10 Were you nervous at all about being able to pull this off?

00:46:13 Oh yes, I think I was, certainly at the beginning,

00:46:19 because it was an unfamiliar environment to me.

00:46:25 It was done in the Royal College of Surgeons, in fact.

00:46:29 I had to give two lectures, one after the other,

00:46:33 because of the cameras and so forth and the timing.

00:46:37 I remember the producer, who was another, James McCloy,

00:46:43 coming in about ten minutes

00:46:45 before I was about to give the first lecture,

00:46:48 who had an audience instead,

00:46:51 and I had a bench full of molecular models and so forth,

00:46:56 which I was going to talk about and show,

00:46:58 and I'd rehearsed it, I'd got it all worked out in detail,

00:47:01 and he said, oh no, we'll have to get rid of all those.

00:47:06 So within about ten minutes of starting the lecture,

00:47:12 he wiped out the beginning of my first lecture.

00:47:16 So what did you do then?

00:47:18 I gave it in a different way, with fewer models.

00:47:22 This is the sort of thing that sometimes happens.

00:47:25 You can't design when I would be...

00:47:30 Nowadays I would be a little firmer with the producer,

00:47:34 I think, if that happened.

00:47:36 As a matter of fact, he was probably right,

00:47:38 but I would have appreciated a little more time

00:47:41 to digest the instruction.

00:47:43 He'd only just breezed in, he hadn't been in it before that.

00:47:46 But these were very well received, weren't they,

00:47:48 in the previous lectures?

00:47:50 Yes, I think, in some ways,

00:47:53 I've got much more experience since,

00:47:57 and I've learnt a lot of my mistakes and so forth,

00:48:02 but in some ways the subject was the most interesting I've given.

00:48:08 It was a single, homogeneous, very hard bit of science,

00:48:14 which I put over to the public,

00:48:16 and it did seem to go.

00:48:19 I don't think anyone had thought of thermodynamics,

00:48:22 because I did the thermodynamics fairly thoroughly, really,

00:48:25 as a popular subject before, and it seems to have been.

00:48:28 I remember walking once into, just after these had finished,

00:48:32 walking into the airport in London,

00:48:36 coming back from somewhere,

00:48:38 and it was empty about midnight,

00:48:41 and four or five tough old porters

00:48:47 were at the other end of this huge hall,

00:48:50 and one shouted,

00:48:52 What's new in thermodynamics?

00:48:55 Did you tell them?

00:48:58 But you went on to do lots more television.

00:49:01 You actually, for a while, were the scientist of television.

00:49:05 You did enormous numbers of programs.

00:49:08 Quite a lot, yes.

00:49:10 And people really did appreciate them,

00:49:13 and a lot of people would say some of these have not been bettered.

00:49:17 Can you tell me about some of the other programs that you did on television?

00:49:21 Well, I gave the Christmas Lectures,

00:49:27 the first ones of those,

00:49:29 Christmas Lectures at the Royal Institution,

00:49:31 you know, for children, for a juvenile auditory,

00:49:34 as Faraday used to call it.

00:49:37 A first series of those was called Time Machines,

00:49:41 and I talked a bit about flash photosis there, of course,

00:49:45 but I was much broader than that.

00:49:48 There were six hours of lectures of those.

00:49:53 I talked about time in a much more general sense.

00:49:58 And then the other one I gave,

00:50:01 the full Christmas series that I gave,

00:50:03 was called An Actual History of a Sunbeam.

00:50:07 It was on photosynthesis,

00:50:09 and of course the title was sort of stolen a little bit

00:50:13 from Faraday's Chemical History of a Candle.

00:50:17 We did a lot of series.

00:50:20 We had a series running for five years that I was chairman of,

00:50:24 called Controversy,

00:50:26 which was on largely scientific topics.

00:50:29 It was a two-hour debate.

00:50:32 It was based on the little lecture,

00:50:36 but it was only a mini-lecture for about ten minutes,

00:50:40 and then a debate afterwards with four people opposing and so forth.

00:50:44 More of the modern confrontation type of thing.

00:50:48 And then for some nearly 20 years,

00:50:51 I either chaired or took part in the Young Scientist of the Year programs,

00:50:58 which each year was a series of usually about six schoolchildren

00:51:09 showing their projects and having a competition for the best one.

00:51:15 A lot of scientists, particularly chemists,

00:51:18 feel there isn't enough on television about science.

00:51:21 You think it's very important, don't you,

00:51:23 to have this kind of program on television.

00:51:27 Is it because it's very difficult to convey chemistry on television

00:51:32 that it doesn't appear, or do you have any opinions about this?

00:51:36 Well, if you're talking about chemistry, it is difficult, yes.

00:51:39 Yes, it is.

00:51:40 First of all, science in general.

00:51:44 Well, the fact of the matter is that chemistry particularly,

00:51:47 but all of science, to be honest, is not a big pull.

00:51:53 You see, the only measure of success, it seems,

00:51:58 with a television company is the audience rating.

00:52:03 And whereas they can get 12 million for a little stupid quiz show,

00:52:11 if they won't get more than a million,

00:52:14 oh no, I think a few more than that,

00:52:16 perhaps for Horizon it may be two million,

00:52:21 something of that order, or even less.

00:52:24 So you're not going to get much more on peak times, you see.

00:52:31 I think my main objection at the moment is that

00:52:37 science just doesn't seem to be part of the culture,

00:52:44 largely because the majority of people who run television,

00:52:47 like people in the media, don't know anything about it.

00:52:50 They don't have any interest in it themselves.

00:52:52 They don't understand what it's about.

00:52:55 And therefore the Committee on the Public Understanding of Science,

00:53:01 which I chair at the moment, is looking into other approaches,

00:53:07 soap opera and things like this.

00:53:09 You see, why doesn't soap opera and many of the serials and so on,

00:53:17 why don't they have some scientific content?

00:53:20 Why isn't the family in the East Enders,

00:53:28 why isn't the son a medical technician or something of this kind?

00:53:33 They never are. These don't come in.

00:53:36 There is one example of that which is interesting,

00:53:38 and that is that the most valuable scientific instruction in agriculture

00:53:47 is given on a radio program called the Archers.

00:53:50 And farmers watch this avidly for information about

00:53:54 what they should be doing to their crops this month

00:53:57 and how they're going to cope with the rain that they've had.

00:54:01 Because they incorporate factual information into this.

00:54:04 Yes, they have proper scientific advice on this.

00:54:07 And I think one needs more science in that.

00:54:10 Another thing that always gets me is when you have a quiz show,

00:54:18 you have something like the Mastermind competition,

00:54:22 and if you have any scientific questions,

00:54:27 they're at the primary school level, and then they can't answer.

00:54:34 Yes, like the university challenge.

00:54:37 Yes, that's right.

00:54:40 So you'd like to see a Dallas-type science soap opera, would you?

00:54:46 Well, it depends what it was like.

00:54:48 But what I'm saying is I would like to see the people who run the media

00:54:54 and choose the programs and write the programs and so on,

00:55:00 being people who have some sort of scientific interest and background.

00:55:07 They don't have to be especially scientists,

00:55:10 but I would like them to be people who know what makes it tick

00:55:15 so that they can write as I would.

00:55:19 If I were writing a story not about science,

00:55:24 science would come in in all sorts of ways, you see.

00:55:28 Let me switch from your interest in science and science television

00:55:33 to your other favorite pastime, which is sailing,

00:55:38 and talk a little bit about the enjoyment you get from that

00:55:42 and particularly about this 32 photos of a boat which you've got.

00:55:48 Well, I think I haven't evolved as far as most people from the fish stage.

00:55:57 I like the water and I like swimming and so forth,

00:56:00 and I've always enjoyed the sea.

00:56:03 That's why I joined the Navy.

00:56:05 I was a radar officer in the Navy.

00:56:07 I was given the choice of the services.

00:56:09 I never had any doubt, and I enjoyed my time in the Navy very, very much.

00:56:14 But it hasn't been a major activity, really.

00:56:24 I've enjoyed sailing when I could.

00:56:27 I was a member of the Cambridge University cruising club.

00:56:31 We sailed firefly dinghies there.

00:56:33 Then when I went to Sheffield, I bought an Enterprise dinghy and sailed that,

00:56:42 raced that.

00:56:43 I did a bit of ocean sailing as a crew, ocean racing as a crew,

00:56:48 rather than as an owner because I couldn't possibly afford an ocean racer.

00:56:53 And then the joy when I, well, the first time I could afford it,

00:57:00 and it was a bit of an extravagance,

00:57:01 I did get a 26-foot sloop when I got the Nobel Prize.

00:57:06 In fact, I told them when I went to Stockholm,

00:57:10 they said, how are you going to spend the prize?

00:57:12 I said, well, some of it, not all of it,

00:57:14 but some of it I'm going to spend on a sailing boat.

00:57:18 And, of course, the Swedes, although this was December,

00:57:21 the Swedes are not slow off the mark.

00:57:24 And looking out of the Grand Hotel window the following morning,

00:57:27 I saw a beautiful boat in full sail coming up the river to the bridge.

00:57:34 And then they came to the hotel and asked for me,

00:57:37 and they brought me this boat to sell me.

00:57:39 It was far bigger than I could afford,

00:57:42 so they'd rigged it and they'd sailed it up

00:57:44 because they'd heard that I was going to buy a boat.

00:57:46 I hope they gave you a trip on it.

00:57:47 Well, yes, just a little one.

00:57:50 So I sailed that, we sailed.

00:57:55 Our home is in Kent, very near to the sea.

00:58:01 When I bought that house when we moved from Sheffield,

00:58:05 I bought a bit of freehold mud as well to keep the boat on,

00:58:09 which is very nice, so that I could walk almost to the boat from the house.

00:58:13 And we can be across in France or Holland or Belgium in daytime in summer.

00:58:20 It's a long trip, 16 hours, but one can just about do it.

00:58:25 So we've done quite a bit of that with my sons.

00:58:28 And then I decided that if ever I was going to be really extravagant

00:58:32 and have a bit bigger boat,

00:58:35 they used to say, of course, that you have a foot of boat for every year of your life,

00:58:40 but that's something that very few can afford now.

00:58:44 But I've just got a somewhat bigger one, a 32-footer, which I enjoy very much.

00:58:54 I don't race it or anything.

00:58:57 We don't sail it so far.

00:59:00 I went with my son and one of my sons and my wife to France last year,

00:59:06 and we enjoyed it very much.

00:59:08 And even if I can't go to France, I've lost my crew,

00:59:11 although I'm getting a new crew because my students,

00:59:14 my present students are very keen on sailing,

00:59:17 so I'm going to be sailing a bit with them.

00:59:20 But even if I can't, just messing about in the boat is always fun, if I have time.

00:59:27 We didn't talk very much about the time at the R.I., apart from the lectures.

00:59:34 You did do some quite interesting work while you were at the Royal Institution,

00:59:40 and you were there for quite a long time.

00:59:42 Twenty years.

00:59:43 Yes.

00:59:44 Do you want to talk a little bit about the days at the Royal Institution?

00:59:48 About the research, you mean?

00:59:50 Yes.

00:59:51 Because we were talking about, I was doing a lot of lecturing and that sort of thing,

00:59:59 and taking an interest in the R.I. itself, which is extremely interesting,

01:00:06 looking after the lectures given by others and so forth.

01:00:09 But research was my main activity there, really.

01:00:16 The two main developments there were, it was at the R.I., really,

01:00:22 that we went into the laser development of flash photoresis.

01:00:29 We built the first nanosecond apparatus there with the first Q-switched laser,

01:00:37 and we first observed the singlet state, which I was talking about earlier,

01:00:43 the very much short-lived singlet state there.

01:00:47 And then into the picosecond region, and now into the femtosecond region.

01:00:53 All this is, it takes time.

01:00:57 And it, one can't, it was now so well, it was so obvious that this is what would happen,

01:01:08 it depended on the new lasers and so on, that I can't claim,

01:01:13 nobody can claim that they were leading the field here.

01:01:17 It was a number of people right at the front, pushing on in different directions.

01:01:23 So I can't claim that we were the first in the nanosecond or picosecond.

01:01:28 I don't think anybody can, because it was all going parallel and still developing.

01:01:32 But it is a very important development, and it was fun.

01:01:36 A lot of new areas were opened up.

01:01:40 And most of all, that's the second thing, it then became possible to study photosynthesis,

01:01:46 which is the, really the most, certainly the most important photochemical reaction,

01:01:54 it's probably the most important chemical reaction.

01:01:57 It's almost the most important thing that happens, because it's the origin of life,

01:02:01 and it provides all our food and energy for life.

01:02:05 So it's pretty basic.