Oral-History:Mary Lee Berners-Lee

About Mary Lee Berners-Lee

Mary Lee Berners-Lee was born in 1924 in Birmingham, England, where she graduated from the University of Birmingham with a degree in mathematics. She later taught mathematics before returning to work full-time in the computing industry. Berners-Lee was an important British mathematician and computer programmer who worked in a team led by John Bernnett that developed programs for Manchester University’s series of Ferranti Mark 1 computers. She married Conway Berners-Lee, who was also part of the team at Manchester University. Their eldest son, Sir Tim Berners-Lee, invented the World Wide Web. After a period devoted to bringing up her children, she became a schoolteacher of mathematics and then a programmer using Basic, FORTRAN, and other languages before retiring in 1987.

In this interview, Berners-Lee talks about her childhood in Birmingham, getting an education during WWII, her astrophysics fellowship in Australia, and her time working at Ferranti.

About the Interview

MARY LEE BERNERS-LEE: An Interview Conducted by Janet Abbate for the IEEE History Center, 12 September 2001. Interview #578 for the IEEE History Center, The Institute of Electrical and Electronic Engineers, Inc.

Copyright Statement

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It is recommended that this oral history be cited as follows:

Mary Lee Berners-Lee, an oral history conducted in 2001 by Janet Abbate, IEEE History Center, Piscataway, NJ, USA.

Interview

INTERVIEW: Mary Lee Berners-Lee
INTERVIEWER: Janet Abbate
DATE: 12 September 2001
PLACE: Berners-Lee’s home in London, United Kingdom

Childhood in Birmingham

Abbate:

This is an interview with Mary Lee Berners-Lee on September 12th, 2001. So, to start out: When were you born, and where did you grow up?

Berners-Lee:

I was born on the twelfth of March, 1924, in Hall Green, Birmingham, and I lived there until I graduated.

Abbate:

What did your parents do?

Berners-Lee:

They were both teachers. My mother gave up when she got married, but my father continued to teach in the Birmingham schools.

Abbate:

What did he teach?

Berners-Lee:

He taught general subjects. He specialized in children who were not very able, which he enjoyed doing.

Abbate:

Did you have brothers and sisters?

Berners-Lee:

Yes, I had a brother, but he was in the RAF, and he was killed in the war.

Abbate:

What kind of schools did you go to?

Berners-Lee:

I went to the ordinary state schools: the College Road Infants and Juniors, and then on to Yardley Grammar School, which was one of the three coeducational schools in Birmingham, most of them being segregated.

Abbate:

I was going to ask, yes.

Berners-Lee:

Yes. And it was a very good school. It wasn’t particularly academic, but it did emphasize making people good citizens; it tried to. And it had what they called “free discipline,” so that I don’t remember any dire punishments: no detentions, no caning, nothing like that; and the discipline was very easy. How it was achieved, I don’t quite know. In my brother’s school there was bullying, and caning, and expulsions, and things like this, but none of that at Yardley. It was a very nice school like that; but not particularly academic.

Abbate:

Were you encouraged by your parents to pursue a career, or pursue further education?

Berners-Lee:

Oh, absolutely. Yes, yes, yes! I think they had met in a meeting for women—votes for women—and were very keen on the rights of women, and thought it was very important that women felt that they had an alternative to just getting married, which was how a lot of people had been brought up and were still being brought up. So, yes: education was very much emphasized.

Abbate:

And were you particularly drawn to math or science as a child?

Berners-Lee:

Yes. I enjoyed English and the languages and so on, but yes: I always had a mathematical bent. Yes. And in England, at sixteen, when you specialize in the sixth form, you did have to choose, so I reluctantly had to drop both French and English, which I tried to keep on with for a bit. I did geography and physics and maths.

Abbate:

So after that—I don’t know if you went to university.

Education amid World War II

Berners-Lee:

Yes, I went to university in Birmingham. It was, of course, by that time the war. I’d been evacuated at 15 to Lidney in Gloucestershire, on the Severn: a very depressed little town. It had been a port on the Severn, which had imported tin from Cornwall (which had long since ceased to be important) and used the coal from the Forest of Dean and had a tin-plating works that was quite important. The tin-plating works was still there, but only just; and of course it was no longer a port, and the coal came from South Wales, and the tin from—I don’t know, South America or somewhere? So it was a very sad, depressed place, really—but it has the whole of the Forest of Dean as its hinterland, which was extremely beautiful! That first autumn of the war was an incredible autumn, and I have never seen trees like that before. It was gorgeous!

Abbate:

This was ‘39 or ‘40?

Berners-Lee:

Yes, 1939.

Abbate:

So you continued your schooling there?

Berners-Lee:

Yes we did. We shared the school with Lidney Grammar School: Yardley had it in the afternoons, Lidney had it in the mornings.

It was really hard. When all these children landed on Lidney—one of the things [was], there weren’t enough blankets! It was a bitterly cold winter, and we put not only our coats on the bed, but our dresses as well, I remember, to try and keep warm!

Abbate:

So you were boarding at the school?

Berners-Lee:

No, no. We didn’t; we stayed in houses. Our hosts were very kind to all of us city children, fitting us in with their families.

But at the end of a year, we came back to Birmingham. A lot of it had been the “phony war,” of course, with nothing happening, but when we got back to Birmingham, one of the first things that happened was that the school was hit! One wing had gone, and the central heating had gone, and the water came in all over the place because the shrapnel had made holes in the roof; so we had duck-boards on the floor, and would wade along, and spent a lot of our time in the air-raid shelters. And the Maths Department suffered, because it was mixed staff, of course—men and women—and the men all joined the army; so in that two years, I had five different maths teachers—which is not recommended! And then I wondered what to do, and the government was offering bursaries for engineering, and I had a bursary to go to Manchester and do engineering.

Abbate:

A bursary is a fellowship? A scholarship?

Berners-Lee:

Yes, yes. Paying everything.

Then I realized at the end that I was not an engineer, I was a mathematician, and I ought to do what I wanted to do; and so I did that at Birmingham—living at home, and having a grant from a Yardley fund that paid me the large amount of seventy-five pounds a year! That covered my tuition fees and the union fees, and the rest was pocket money. So I was relatively well off, compared with some of my friends who were Jewish refugees there who had twenty-two pounds a year to live on, with their fees paid: twenty-two pounds from the International Student Service.

Abbate:

How did you get the fellowship? Was that competitive?

Berners-Lee:

The school was in the ancient parish of Yardley, which had been very richly endowed in the old times to cover apprentices, so it could be very generous. I’d had my school fees paid—because there were school fees then, even at state schools—and they had been paid, and I’d always had a book allowance while I went through school. Then I got this, because I was just lucky that I lived and went to school in this ancient parish of Yardley, which had large charity money. That was good, yes. But it would have been a good thing to get away from home, I think, at that age; but it was much cheaper not to.

Abbate:

Did you think of going off to join the WRENs, or something?

Berners-Lee:

Well, [back] then one had to get reserved, of course, from military to go to university at all, and you were reserved for two years and got what they called a “War Honors Degree”—unclassified—after two years. By that time, which was 1944, the armed forces didn’t need women any more, and they sent me to Farnborough to the aeronautical research place; but my brother had just been killed, and Farnborough seemed an awful long way away from Birmingham. I wrote suggesting that they send me to Malvern, because I knew there was somewhere similar in Malvern—I didn’t know anything about it really—which was near Birmingham, and I would then be able to get home and keep an eye on my parents. And they did.

I wasn’t happy at Malvern. Everybody else there knew a lot of radar—it was a radar research place—and I didn’t. It had a very good war-workers’ club, which I did enjoy, where we did amateur dramatics, which was a good thing; but the work at Malvern I didn’t enjoy, and of course it was an unhappy time because of the death my brother. I had to stay there for two years, and then I decided to go back to the university. And by this time, I knew what I wanted from the university. When I went up at eighteen I didn’t; I was very immature, and I didn’t know what I wanted. So I went back and did the final Honors year.

Abbate:

So you had spent two years at the university; then you went to Malvern for . . .

Berners-Lee:

Two years. And then I went back for another year—which got me to 1947.

Abbate:

You said you knew what you wanted. What did you want?

Berners-Lee:

I was perhaps more interested in maths. It’s difficult to say, isn’t it? I think I had just been like a sausage in a sausage machine at first! But I knew more what I wanted, in that way: I was interested in maths.

Astrophysics Fellowship in Australia

Berners-Lee:

But when I graduated, I was really fed up with the war, and I suppose fairly romantic, and I had always been interested in astronomy, and I wanted to go into astronomy. It is, of course, a very romantic subject. I read an article in the Monthly Notes of the Royal Astronomical Society by a Dr. [Richard van der Riet] Woolley in Australia—in Canberra, Mount Stromlo—and wrote. And he took it up and gave me a fellowship to the observatory in Canberra. It is an important observatory, because it is in the Southern Hemisphere, and there weren’t many there, and of course the Southern Hemisphere has a very much bigger section of the Milky Way, so there are many more stars in it. The observatory was a solar observatory, but it did stellar work as well, of course. Canberra was a beautiful place! I went out—Dr. Woolley had written to, I don’t know, the officials in government, saying how could he get a student out cheaply? And they suggested I come out as a migrant, for ten pounds! Australia then was trying to attract migrants (unlike now) from all over the place, and you could have a passage for ten pounds. You had to agree to stay for two years; otherwise you would have to refund the passage. So I went out on the first all-immigrant ship, the Orion, which got feted when it got to Freemantle, and then went round the south coast to Sydney, where Dr. Woolley and his wife met me. [They] took me up to Canberra, which is a couple of hundred miles away and two thousand feet up—and has a very good climate, because the air is so clean and fresh; and all the wonderful Australian bush! That was absolutely marvelous. So I really enjoyed that. But astrophysics was not my line.

Abbate:

What did you actually do for them there?

Berners-Lee:

Some people in Harvard had classified the stars in a two-dimensional array, by magnitude and radius. [Arthur] Eddington’s theory of the internal constitution of the stars, which had come out some time before, showed that for a mainstream star—an ordinary star—if you know two things about it, you can determine the others. The magnitude is the apparent brightness in the sky, and that of course is affected by the distance away; and there’s the true luminosity, the radius, and the mass. But only two of those are independent, and if you can find those, you know the others, by the theory of how the internal constitution works, with the hydrogen being used up at the center of the stars to provide the luminosity.

Harvard had established some standard stars, in the Northern Hemisphere, to be used to classify the others. Some of these stars were visible from the Southern Hemisphere, and the Mt. Stromlo Observatory had an enormous number of very good slides of stellar spectra that had been taken previously. They needed classifying. So they set me on this. I should have protested!

Abbate:

You should have protested because it was dull?

Berners-Lee:

Yes. And I discovered afterwards that it was decided to give it to me because no man would have the patience—and that was appalling. I didn’t discover that until after I’d left. I was told that.

But also, I now realize that in other ways it wasn’t the job for me, because I am singularly bad at pattern recognition. I read very slowly; I don’t remember faces; I can’t recognize patterns at all well; so I was the last person to do it. But I hadn’t realized that at the time, and I had tried to fit a square peg into a round hole. So my three years in Australia were in some ways immensely enjoyable, because I really liked Australia; and when Dr. Woolley came to Europe for six months, he lent me his horse, which was very good fun! I loved the camping and the outdoor life, and had good friends there. It was a young place. Very few people had been born there; they came and went. You went to a lot of farewell parties, and after a time you decided that the next one would be yours.

When I came back to England—my mother wasn’t very well, which was another thing that brought me back—I didn’t really quite know what to do, because I didn’t want to work on stellar spectra. Although I had this skill, I didn’t want to use it. I was wondering what to do, and looking around. I saw the advertisement in Nature saying, “Mathematicians wanted to work on a digital computer.”

First Computer Programming Job

Abbate:

So you had not, before this point, ever had any encounters with computers?

Berners-Lee:

No! I had thought that with the catalogs of stars, they ought to be on punch cards—when I’d heard about punch cards—but I didn’t do anything about that. But no, I didn’t know anything about them. I’d only used Brunsvigas, mechanical calculators.

Abbate:

So you saw this ad . . .

Berners-Lee:

Yes, and went to the Birmingham Reference Library to find out what a digital computer was. I spent two days in the Reference Library reading about it, finding it very interesting; applied for the job; went for an interview; and, because I knew something about computers, I could ask intelligent questions—and this must have increased my initial salary by a factor of about a third, I think. When I got there, it was thoroughly enjoyable. When I went for the interview and took a bus out from the middle of Manchester, out along the Oldham Road, I thought, “Never, never, never will I live in this ugly place!” I had, of course, been living in Canberra. But by the time the interview was over I had changed my mind, and I was really happy in Manchester. So I now know that happiness is not really in the beauty of where you live; it’s in other things.

Abbate:

So you were working for the University at this point?

Berners-Lee:

No, I was working for Ferranti. What had happened was that the university had built the computer, and Ferranti offered to make a properly engineered commercial version. They were building the first one for the university itself—this was the Ferranti Mark 1—with a view to selling other ones afterwards. When I went there, the university had already got the Mark 1—just. [We were] working out at Mostyn . . .

Abbate:

What was that again?

Berners-Lee:

M-O-S-T-Y-N, I think. It’s out on the Oldham Road, running North from Manchester, not very far, an industrial area surrounded by cotton mills. Local people preferred working in the cotton industry. If the cotton industry was doing well, Ferranti found it difficult to get labor on their radio belt.

Abbate:

So you were actually in the factory?

Berners-Lee:

Ferranti’s main line was big transformers for the electrical grid, and they were on a different site; they were at Hollingwood. But the Mostyn factory made radios. There was a belt on which the radios travelled; and girls were soldering on components very monotonously as the belt moved.

The engineering team was housed in the main body of the factory, but the programming team, which was part of the sales department, was in a small prefabricated nursery school that was established in the yard. It was known as the Tin Hut, although it must have been made of asbestos, I think! [laughs] Young people were recruited. It was a very good team—very exciting!

Abbate:

And what were you actually hired to do?

Berners-Lee:

To program—in machine code, of course; there wasn’t anything else. One of the things I did was to do simultaneous equations—what were thought of as large numbers of simultaneous equations. Forty, in fact, which was then unthinkable: to be able to solve forty simultaneous equations at once.

Abbate:

And what application would that be for?

Berners-Lee:

Aircraft. Aircraft design was one of the big applications: working out the stresses along the wings, and things like this.

Abbate:

So you were supporting scientific users?

Berners-Lee:

Oh, yes! They were only thinking of scientific use. Yes. One wrote in machine code, using the binary code from the teleprinter tape, so one learnt it by heart. The machine, of course, worked in binary, and had Williams storage tubes, which were cathode ray tubes displaying dots as ones or zeros in blocks of five, and the teleprinter tape had five hole-positions across the tape for each character.

Abbate:

Right, so five bits for the characters . . .

Berners-Lee:

Five bits, which gives you 25 = 32 possible patterns of noughts and ones, that is 32 characters. So you had the 26 uppercase letters of the alphabet and six more. I can't remember all the code now, but a row of five zeros was / [“stroke”]; 1 in binary was “E”; 2 in binary was “@”. It began /E@A:SIU..., ending with zed for five ones (31 in binary).

The machine had that very clever invention, the B-tube. Have you heard of B-tubes?

Abbate:

I don’t think I have.

Berners-Lee:

All the data and the instructions are stored in the computer as binary numbers. The Ferranti machine had three special registers, A, B, and C. A was the accumulator where the answer was put. C was the control register which said where the next instruction was to be found. But the B could be used to contain a number to be added to the instruction to modify it. As a simple example, if you are trying to total a column of figures, you have to pick up the first and put it in the accumulator; add the second one to it; and then pick up the next one and add that one to it. So you’ve got a little instruction which says, “Add into the accumulator first the number in Line 1, then the number in Line 2, then the number in Line 3.” And in the B-tube you could keep a counter, so what you actually said was, “Add line n into the accumulator”—where n is modified by a B-tube—“and then add one on to n, and then test to see if n has reached your maximum.”

But of course, having got this B-tube that could add onto the instruction, you could also—it was very cunning—actually alter the function part of the instruction so that it no longer said "add." And that made the program extremely difficult for anybody else to follow, but very good fun to write! [both laugh]

Abbate:

So that must have been quite an arcane skill, in a way.

Berners-Lee:

It was very good. And space was at a premium, because . . .

Abbate:

“Space” meaning memory?

Berners-Lee:

Yes, the space in the fast memory. You didn’t have very much: two blocks—how much was a block? And otherwise you had to read from the drum, and that took a long time, so you tried not to do that too often. You had to be very cunning with getting things into a small space.

And of course it was very difficult getting the program right. But what you could do on that machine was make it go through one instruction at a time, and watch actually what was happening on the cathode ray tubes. But that, of course, took a lot of computer time, and you would have people in the queue waiting to use the computer behind you. There was a big notice over the computer—I think it was [a play on the one] devised by IBM— which said, “Think—but not here!”[1] [both laugh]

So, John Bennett got me to write a program to print out the state of the computer: what was in the accumulator, the B-tubes, and any other data, at any point. This thing was a very early diagnostic program called “Stop and Print.” That had to run—using absolute minimum of space—monitoring the program it was testing.

Abbate:

So you could have two programs running at once? Or did you combine them somehow?

Berners-Lee:

No. The computer was simple and could perform only one instruction at a time. There were no sophisticated operating systems like Windows or even MS-DOS. In machine code, the test program had to act as master, running the program it was testing as a slave. One of the stores had to be a permanent thing. We didn’t have a “shift” function in the code, and so you needed the powers of two stored. You also needed a routine-changing sequence, which would change one routine for another. It was just for writing to the drum the program you’ve got and bringing another one down from the drum. So there was one block in the store that was known as the “Perm,” the permanent store. Each line had forty bits, and the block, I think, had sixty-four lines. Alan Turing had written this—it was known as “Turing’s Perm”—and it had the powers of two and this little routine-changing sequence.

What I did was to have a different routine-changing sequence. I still had to leave the powers of two there, because everybody used them, but instead of having Turing’s routine-changing sequence, I had my little program. It took in data from a punch tape, little by little, as the program went, and the punch tape would say, “Substitute for a certain instruction in the main program a jump into my program.” Then I would be able to use the whole of the Perm to bring down another routine, which took in from tape what was needed to be printed out, and printed them out, and then returned to the master program. I just had this one little cathode ray tube that I could use: one little block of 64 lines!

Abbate:

Was that your idea, to come up with this method of doing diagnostics?

Berners-Lee:

The original idea came from John Bennett, who was an Australian, and who was in charge of the programming. A very, very able man, who later went back to Australia and became a Professor of Computing Science in Sydney. But I did the programming, which I thoroughly enjoyed.

[RECORDING PAUSES]

Abbate:

We’re back.

The Fight for Women’s Rights at Ferranti

Berners-Lee:

One of the things that was really interesting in Manchester, though, was the fight for women’s rights.

Abbate:

Really?

Berners-Lee:

Yes. We discovered—I think there were slightly more women than men (I’m not sure about that), and we discovered that the men were getting paid more.

Abbate:

This was at Ferranti?

Berners-Lee:

Yes. And we were horrified! Ferranti was a very paternal firm. They were shocked that young graduates did something so unprofessional as to discuss with one another what they earned. “Dearie me!” [both laugh] But their argument was that if they knew that Joe Bloggs had a sick wife and real trouble, then they could quietly give him more—provided nobody talked about their salaries, and they couldn't do that in the open—and that a man would have to support a wife and children, and so needed more money than a woman. Well, this went nowhere with the professional women. I used to hear the inside, because at that time I was sharing a flat with the Assistant Personnel Manager for Women, and so a little communication went through this route. I knew what they were thinking in the Personnel Department; and I was the person who was selected to go and see the management and make the case—and we won that.

Abbate:

So what was the outcome?

Berners-Lee:

We got equal pay! All the women got raises, to be equal with the men.

Abbate:

So at that point, did a given job position have a given salary?

Berners-Lee:

It wasn’t strictly laid out, like that in the Civil Service, but the principle was accepted that the young graduates coming in should have the same [salary], whatever the sex; and with promotion, the same raises. They accepted the principle of equal pay, which they hadn’t before.

Abbate:

What year would this be, more or less?

Berners-Lee:

This would be—I joined Ferranti in ‘51; this might have been ‘52? Something like that. So, that was a good thing to do.

We also had to fight for women’s rights later on. Ferranti had built the computer to the University's design for the University; Ferranti shared the use of it, but as the computer at the university got used more and more and more, Ferranti got restricted in the hours in which we were allowed to use it. It became evening hours, and then later, the university would only let Ferranti have it between midnight and eight in the morning. And it was decreed by the Personnel Department that women should not be there at night—to the glee, I remember, of one particular member of the male staff, because it meant there was more time on the computer for the men! But of course, [for] the women, it was a disastrous idea. Unfortunately, the Personnel Manager knew that we were there at night, because I shared the flat with the Assistant Personnel Manager, and I started coming in late, and I wouldn’t get in till ten o’clock in the evening, and then midnight, and then later; and one time I hadn’t even come in by the time she went to work in the morning. And the Personnel Department knew about this, and they thought we ought not to work after about ten o’clock or something. But we managed to overrule that. The Personnel Department then suggested that we needed a chaperone, I think—because the maintenance engineers, of course, were always there, and they were men—and suggested we had a tea lady. We managed to override that one as well! [laughs] So we used to get through the night on black coffee!

Tensions between Programmers and Engineers

Abbate:

How many people would be using the computer at night, at a time?

Berners-Lee:

Well, only one used it at a time, of course; but I think there might have been two or three taking turns. And we did get camp beds, so that you could flake out.

Abbate:

“Flake out” is “lie down”?

Berners-Lee:

It’s a little slang. Yes, “lie down and go to sleep.” And it was awful to be woken up. You’d be in a very deep sleep, and to be woken up—although you were dying to get on to the computer—to be woken up in the middle of the night was not very good, when your turn came! However, it was worth it. You had black coffee, and had to go on the computer.

The other interesting thing that happened was the argument as to what made a real proper working machine. One of the things the machine would do: you would look at this cathode ray tube with its patterns of noughts and ones on it, and ones would sometimes sweep across from one side, because the machine was going wrong, and the whole tube would fill up with ones. Or sometimes it would just accidentally drop a one in; it was known as a “clod.” Then you would have to call the engineers, and there was a big row: because on the one hand, it was extraordinarily difficult getting a program right, and you couldn’t believe that you hadn’t got your program right, so you thought it was the machine that was wrong; and then often you’d find that it wasn’t. But it was quite difficult deciding which, and so there was tension between the engineers and the programmers. I mean, on the whole, on the personal basis, we got on with them very well; but there was a big row about whether the fault was the machine or the program. Sometimes they were right, and quite often we were, but they thought we were always wrong! [both laugh] The machine had a nice little humming noise, so you could tell what program it was running by the sound it made. And sometimes if you were sure that it was the machine that was wrong, you would run the engineers’ test program—and the engineer would be around in no time, because he’d hear it! He’d know the little song that it sang. You couldn’t do it secretly. [laughs]

There was a big row: I was trying to invert a 40-by-40 matrix, row by row, and I just couldn’t get it through, because the machine always made a mistake before we got to the end. And the input and the output were not compatible, so I couldn’t just output the half-inverted matrix to re-input it another day—not without writing a very complicated program to do it. So I found myself very much in the middle of this big row between the engineers and the mathematicians as to what constituted a really working machine. And I got very tired over it. One time I went along to see a professor at the university about this, to state my case. He was very polite to me.

Abbate:

Who was this? Do you recall?

Berners-Lee:

Yes, I do recall! I wasn’t sure whether I want it on the recording . . .

Abbate:

You don’t have to say if you don’t want to.

Berners-Lee:

Well, it was Tom Kilburn.

Abbate:

Oh, right! Right.

Berners-Lee:

The great Tom Kilburn. He was very courteous—and at the time I felt resentful, because I thought he’d been courteous to me instead of arguing with me because I was a woman. I resented this, and I had resented it for years; but when it came to the 50th anniversary of the Manchester computer, and we went back, and there was a really good dinner, and I’d had enough wine, I went and tackled the great man and told him this. And he said, “Oh, no, no, no! I wouldn’t have been like that. I didn’t argue with you because I knew you were right!” [both laugh] So one can be very sensitive about this feminine issue, you see.

Abbate:

Did they make any changes to the machine because of that?

Berners-Lee:

Oh, yes! They made the machine much more reliable; they had to. And now, of course, they’re incredibly reliable—but it was a battle.

Abbate:

Now, the computer in Manchester was the Mark 1.

Berners-Lee:

And then the Mark 1*. They sold [a commercial version of] the Mark 1.[2] One went to Toronto. The boss of the Sales Department in the Tin Hut was Vivian Bowden, who later became Lord Bowden, and he edited Faster than Thought.[3] Do you know Faster than Thought? I’ll show you it afterwards.

Abbate:

I think I’ve heard of that.

Berners-Lee:

He was an amazingly able man, with a very good sense of humor. I don’t know how many we sold of those Mark 1’s—not very many—but Mark 1* was certainly sold; quite a lot of them. Yes, there were quite a lot of Mark 1*s sold around to the aircraft industry. I can remember a few places, but not very many. Fort Halstead certainly had one, because I used that one. One went to Italy. I would have gone to Italy for the acceptance tests, because my program for inverting the 40-by-40 matrix was used as part of the acceptance trial; but by that time I was pregnant, and didn’t go, which was a shame. I would like to have gone to Italy. Well, it wasn’t a shame I was pregnant, but it was a shame I couldn’t go! [laughs]

The Work Environment at Ferranti

Abbate:

Did you meet your husband at Ferranti?

Berners-Lee:

Yes. In fact, we were introduced to each other three times before we realized we’d met before! [both laugh] He joined the London office of Ferranti and was brought up to Mostyn and was introduced to us, and then one time when I was down in London, I had to see him about something, give him something or other, and I met him again. Then when he came up to Manchester the third time and we were introduced again, we suddenly realized we had met before.

Another thing I remember about him was that when I had been working all night on the computer, and he needed to ring up for the results, and I was in the room with the teleprinters going: I could hear what he said on the phone in spite of the teleprinters. Whether that was why I married him, I don’t know! [laughs]

Abbate:

Was that unusual?

Berners-Lee:

Oh, very! It was very difficult to hear with the teleprinters going. They were very clattery machines. Dreadful!

Abbate:

So it was quite a noisy environment to work in?

Berners-Lee:

Yes.

Abbate:

Was it hot as well?

Berners-Lee:

No. It had to be temperature-controlled for the computer. The computer was very sensitive. No, it wasn’t hot; it had to be cooled. I don’t remember trouble with that at all. But of course, they were vast cabinets. But you know all about that.

Abbate:

What were some of the main projects that you worked on?

Berners-Lee:

Well . . . I don’t remember much else besides that. What I do remember was Sheila Horton being asked to do a wages program, and my thinking “Oh, poor girl!” And that was the very first business program. And of course now . . .

Abbate:

How long were you at Ferranti?

Berners-Lee:

I came down to the London office in the end of 1953, I think, because Ferranti opened an office in Portland Place, opposite the BBC in a lovely Adams building. They had been going to put a Mark 1*, so they reinforced the floor, but then they put in Pegasus, which didn’t need the reinforced floor. And that must have been the end of ‘53, perhaps; or it might have been ‘54. We married in ‘54, and then I worked until May ‘55, and Tim was born in June ‘55.

Cottage Computer Programming

Berners-Lee:

After that, I did do some cottage-industry programming. If somebody had a nice, neat little project, I could program at home and then go to a computer somewhere to test it. That was good fun!

Abbate:

Were you sort of in business for yourself?

Berners-Lee:

Yes.

Abbate:

In the sense that you were getting contracts from former [employers].

Berners-Lee:

Yes; and [my husband] Conway had contacts, too, you see; and the people at work knew me.

Abbate:

Was that common, do you think?

Berners-Lee:

No, because there weren’t very many women in that position. No, it was early.

Abbate:

But you wanted to keep working.

Berners-Lee:

Yes. I thoroughly enjoyed it! And it’s a tremendous shock, having been professional, to be at home as a mum; and it’s nice to go into the adult world occasionally. Yes, I did find it quite difficult. But in those days, they certainly felt it was better for a mum to be at home with the baby—and I’m glad I did; we had four children, and I enjoyed it very much. But it does break things [one’s career path].

Abbate:

Did you find that work was suitable to doing at home?

Berners-Lee:

Yes. Oh yes, it was. And later on, of course, Steve Shirley started F International.

Abbate:

Right.

Berners-Lee:

You know about it?

Abbate:

I spoke with her last spring.

Berners-Lee:

Ah, right! Yes, well that was a marvelous organization, but it was a bit late for me.

Abbate:

Right, yes. That was quite early for you to be doing contract work part-time. I think that was quite unusual.

Berners-Lee:

Yes.

Well, that was when I helped the men program the bus-bunching job: how to sort out the traffic problem in London transport.

Abbate:

That was when the London Transport Authority asked you to help them?

Berners-Lee:

Yes. They had a simulation of the bus route and the holdups—the random holdups that can happen in the bus route—and they were trying to work out what conditions would stop the buses from bunching; and I helped them program it.

And there was a program for Boscomb Down, the military place, which used to send off weather balloons, I think. It was a program to do with tracking the weather balloons as they went up, and it was for translating the readings.

Abbate:

This was what Down?

Berners-Lee:

Boscomb Down, in Salisbury Plain. It’s a military base of some sort. There was also one for working out mathematical tables, where we had a lot of difficulty with having to be careful about the rounding-off errors. I can’t remember any others, but there were others.

What did happen, too, was that of course the computer industry on the engineering side was going ahead leaps and bounds, and I kept on having to learn a new autocode—a new code—for a new machine.

Abbate:

When did you start getting to program in higher-level languages?

Berners-Lee:

I did Mercury Autocode. Goodness knows! I think I did some ALGOL at some point, then, but I didn’t use FORTRAN until later—much later, when I went back to computing full time.

Going Back to Work Full-Time

Abbate:

When did you go back?

Berners-Lee:

What happened was that when my youngest was about eight or so, the children didn’t really need me all the time at home, and I wanted to do something; but I wanted to be the last out of the house in the morning and the first back in the afternoon, and the school holidays: so I taught for a bit. I enjoyed that, but then the school got reorganized and became comprehensive, and became very tiring. I was teaching maths, of course.

Abbate:

This is at a secondary school?

Berners-Lee:

Yes. I was teaching at a girls’ grammar school—my first experience of a girls’ school, which was interesting!—and it became large and comprehensive, instead of being small and selective. I found myself teaching a fourteen-year old who didn’t know how to add on ten, and I didn’t know how to teach that. I mean, you only have them for a half an hour, forty minutes, or something. I felt if I had her in the kitchen, and was cutting up a slab of margarine, I could have taught her about numbers; but I didn’t feel that it was my job, and it was extremely tiring. And I am a slow reader, so I was a very slow marker. I decided that there were other things to do with life, and went back to computing. Then it was FORTRAN.

I worked for a company that did PERT [Project Evaluation and Review Technique]. Optimizing things: for something like a shipyard that has a big operation, and you have to work out which tasks have to follow which, and so which tasks are on the “critical path.”

Abbate:

Right, right: critical path.

Berners-Lee:

That’s right. That I enjoyed very much.

Then I found that the young people coming along were quicker at programming, and nobody—absolutely nobody—was writing the programs up. Nobody was writing a manual. So I started to set an example that you should write a manual; and this new generation had not learned English, and I found myself writing the manuals.

Now I know why it’s difficult to write a manual, and why manuals are so bad! I found that I was first wanting to get the information down, so that it wasn’t lost—and that wasn’t very readable. And so I went through it again, of course, and made it readable—but it wasn’t very good. I needed to write it again to produce the good copy. By that time, they’d changed the program! [both laugh] So it’s very difficult to get a manual out, in the time available, that is good. And that’s why it’s difficult: the program changes too quickly. It’s also difficult to know what assumptions you are making, which to you are second nature, but somebody else doesn’t know at all. And in the end, I felt that the programs needed rewriting from scratch, and I thought, “Tsk! I’m going to retire!” [laughs] Which I did!

Abbate:

And this last job: Was that a military . . . ?

Berners-Lee:

No, no. It was a firm called K and H. It was private.

Abbate:

The PERT project wasn’t military?

Berners-Lee:

Oh, no! No, all sorts of people needed PERT. Anybody who had got a large and complicated organization, and needed to work out the critical path. I mean, they were big organizations.

There was branch in America. We had close links with America.

Retirement

Abbate:

So you finally retired in the seventies?

Berners-Lee:

No, no. I’m not as old as that! [laughs] 1987 I retired. I think I was 62 and a half. I thought that was a fair age: because women retired at 60 and men at 65, so I felt 62 and a half was fair! And Conway had just retired.

Abbate:

Well, I didn’t know if you’d retired because you’d reached that age, or if you just were tired of writing manuals.

Berners-Lee:

It had got a bit stressful; and I had tinnitus in my ears, which I noticed was getting worse, and I thought, “It isn’t worth [losing] my hearing, this isn’t.”

Abbate:

Because it was noisy there?

Berners-Lee:

No. The tinnitus, I’m sure, was stress-related. The year before I’d had an operation for cancer, and that had oddly enough been a most relaxing time, because everybody was so good. You know, people at work said they’d do my work for me, I wasn’t to worry; and people at home were looking after the house for me; and I was looked after; I had no worries—and I noticed the tinnitus went. So I knew it was stress-related (although the medics never agreed with me!). So I thought if the stress at work was making the tinnitus worse, it wasn’t worth it.

On Training

Abbate:

I have a couple of questions. How were you actually trained when you took the first job at Ferranti, and you had never programmed before?

Berners-Lee:

I had to be shown how to do it. I think then we reckoned that people weren’t any use for six months. It took you six months, doing it on the job.

Abbate:

Really!

Berners-Lee:

Yes.

Abbate:

So they’d show you some basics, and then you’d sort of just try it?

Berners-Lee:

Yes, yes; and you gradually acquired the skill. Yes. I’ve forgotten that. I can’t remember quite what I did at the beginning.

Abbate:

Did you ever feel that as a woman, you didn’t have equal access to training, or promotion, or other sort of benefits?

Berners-Lee:

No, no, Not at all, then. No, not after that.

Abbate:

Once you’d resolved the pay issue, it seemed pretty fair?

Berners-Lee:

Yes. Oh yes; that idea was then accepted. That was good.

Computing as a Family Affair

Abbate:

Are there any particular accomplishments from your computer work that you’re most proud of?

Berners-Lee:

Well, quite honestly, the biggest contribution I’ve made to computing is to be the Grandmother of the Web, isn’t it? [both laugh]

Abbate:

You’ve had four children, and one of course is Tim Berners-Lee, who’s the “Father of the Web.” Did any of your other children go into computing?

Berners-Lee:

Oh, yes. One, the youngest, is a rebel, and didn’t! But the others all have, the other two. Pete is in computing, and Helen is. Yes.

Abbate:

So really the whole family—both parents, and three out of four children, in computing.

Berners-Lee:

Yes. Mike, who’s the rebel, uses the computer, of course; and for his firm, I notice he’s doing the Web pages! But that’s not what he thinks life is about. He had to be the rebel.

We had one Christmas staying with a friend of mine who’s a historian, and she listened to the family conversation, and she was amazed: I mean, I hadn’t noticed, but it had a scientific-mathematical bias—of course, because we were interested. And she said if she’d brought them up, they would all have been historians! [laughs] I don’t think she’s right. I don’t think she’s right. Not at all!

But if you are interested: When I was teaching, I had an awkward class once. They had taken the O Level exam at sixteen, and the next year they were going to go on to the sixth form, but there was that awkward period at the end of the summer. I think now they’re let off school, but then they used to have to come, and you had to try and find interesting things for them to do. So I decided one time to show the class how to find a square root numerically, because I thought this was a very interesting thing to do. We were doing this, and then one of them says in the middle of it, “What’s the point?” I then told them why I’d thought it was a good idea. I said that my daughter and I had been discussing [how] she wanted to make a skirt. She wanted to do a skirt that was flared: it was sort of straightish from the waist, and then had a gathered layer, and then below that was much more fully gathered. We knew what the diameter was around her hips, and we knew what the diameter was at the bottom, and we wanted the ratio in the middle: we wanted the square root of that ratio. And the log tables were upstairs and we were in the kitchen, so we did it numerically, and this is what had given me the idea. They just looked at me absolutely goggle-eyed that I should have this sort of goings-on with my daughter, who was about the same age as they were! [both laugh]

Abbate:

Did they appreciate the practical application?

Berners-Lee:

[laughs] I think they just thought we were mad!

Abbate:

What have you found to be the most satisfying aspects of working with computers?

Berners-Lee:

I certainly enjoyed programming in machine code, I think, as I’ve not enjoyed anything else. It really was such good fun—because it had so many things you could do. But it was slow, of course; it wasn’t efficient. You can’t go on like that. But it’s very neat and nice, in the true sense! Yes.

Abbate:

Because it’s more open-ended . . . ?

Berners-Lee:

It has to be very precise. And of course it’s coded, so you have to be able to read it. It has a lot of skills. I have enjoyed other programming too, of course, but that was very satisfying.

Abbate:

You look like you had a lot of fun doing it, as I’m talking with you.

Berners-Lee:

Yes, yes. And we were a good group, too, socially.

Abbate:

Did you have any role models or mentors who encouraged you to keep up with computing, or helped you through the rough parts?

Berners-Lee:

I haven’t kept up very well.

Abbate:

Well, I mean when you were working.

Berners-Lee:

No, I can’t think [of any]. There was a lot of encouragement. I mean, my husband encouraged me a lot, and later on the family did. Because if you’ve spent sixteen years as a housewife and a mum, you lose confidence; and it was the family, very much so, that encouraged me to go back.

Abbate:

Really!

Berners-Lee:

Yes. Well, I was teaching at first, of course, and the school that I went to asked me to teach sixth-form applied maths. My first reaction was, “Well, I hadn’t done that for years and years and years; I can’t remember it.” Then I realized they hadn’t got anybody better, and so I took it on. [When] I’d be stuck and not able to do something, I’d say, “I’ll have to think about this overnight,” and come and get my husband, who’s a real mathematician, to show me how to do it. I just have a maths degree; I’m not a real mathematician! [both laugh] And of course, Tim was the same sort of age as my students, and knew, and he could help me with—the modern maths had come in then, which I hadn’t learned.

Abbate:

Right: the “new math.”

Berners-Lee:

He would sort me out over that, and help me to get that right. So it was quite good fun around the table, all of us doing our homework! [laughs] Before I taught, I worked through the examples in the book. We were on holiday in Wales, at a country cottage, and I tended to be the first up in the morning; and I would sit out in the sun working through the examples, and then bring up the ones I couldn’t do at breakfast time—get the family to sort them out for me. Very useful. Yes, you need backing if you’re going to do that. I had a lot of backing.

Abbate:

Was it hard to balance work and family responsibilities?

Berners-Lee:

[When I was] teaching it was, because of the marking. I would find myself marking in the small hours of the morning, and that was difficult. But [after I returned to programming], no: because the children got older, and they were interested that I was doing it; they were keen that I should, and very helpful. Yes.

On Changes in Computing

Abbate:

What strikes you the most about the way the field of computing has changed since you’ve started?

Berners-Lee:

Well, of course, it is the very high-level language, isn’t it? And the use of the mouse. You don’t need—well, you do need keyboard skills; I think it’s a great shame that people aren’t, very young indeed, taught how to put their hands on the keyboard. The first couple of hours you spend on the keyboard are very important, and now you do that when you’re about five or six, and somebody should teach you how to put your hands on them and use the right fingers: because you’re going to do it for the rest of your life, and you’ll have less back-ache and more efficiency if you know how to type! But when you have a keyboard like you’ve got [on your laptop], with the mouse below the keyboard: we’ve got one like that, and I find that if you type as you’re supposed to, you rest the heel of your hand accidentally on the mouse, and something dreadful has happened to the screen! [both laugh] You have to be a bit careful.

[pause] I think it’s very sad that more women don’t go into it, and when I was teaching, I did think the girls got put off because girls are less likely than boys to press the buttons to see what happens. And that really is the way to learn—rather than the manual, which is probably inadequate; or the help screen, which is even worse. You really have to learn by experiment.

Abbate:

Do you think you’re the kind of person who would sit right down and bang on the keys and see what happens?

Berners-Lee:

No, I think I’ve had to try and teach myself to do that. I’m much more inclined to try and read the manual and get it right.

But I have got out of date, which I do regret. When I retired, I didn’t really want to spend my time shut in at home looking at a computer screen, and I decided I wanted to be with people. I’ve quickly got out of date, and it’s now quite difficult to pick it up again, [though] I have had a go, after a fashion. But it was a mistake; I should have stayed in it. It’s much more difficult now, and of course as you get older, it’s more difficult to learn.

On the Status of Women in Computing

Abbate:

Do you think computer jobs or getting into the computing profession has become more difficult for women since you started, or easier?

Berners-Lee:

I wouldn’t have thought it was more difficult. No; it’s just that they don’t always want to. I also think—I don’t know what it’s like in America—but I think girls may not be so well taught as the boys.

Abbate:

You mean in a mixed classroom?

Berners-Lee:

Well, either. I’ve always been in favor of mixed education, but I can see that on some subjects, the girls get discouraged. On other subjects the boys get discouraged. So there are arguments for segregating them sometimes. But I certainly found, when I taught computer studies, that the boys would bang away, whereas the girls would want to know what was the right thing to do; and the boys of course would acquire a skill very quickly, and the girls would then think it wasn’t for them—which was a mistake! I don’t know how much of this happens now. When I taught in the girls’ school, of course, the girls were very keen, and they didn’t have this competition from the boys. But playing computer games: if you’re a boy and play computer games, you get a lot of manual skills; and the girls don’t do it. Why should they?

Abbate:

Do you have any advice for young women contemplating a career in computing?

Berners-Lee:

Just do it, I suppose! Why not? Enjoy it!

Do you think they are reluctant to do it, now? They aren’t doing it so much, are they?

Abbate:

Well, obviously many women are going in, though not at the same rate as men.

Berners-Lee:

It has, of course, this problem, that you quickly get out of date; so if you take a break to have a baby, you can find yourself out of date. Also, there was this idea that now with computers, people don’t need to go into the office: it isn’t true. You pick up a lot from colleagues. When I was doing the cottage industry work, I went across to the factory where the computer was to use it, and sat down by the side of the man who was using it, and in no time I picked up half a dozen things that he did; and I realized what a disadvantage it is to be at home. It was a computer I had never used while I was working. It’s amazing what happens, just watching other folk and talking over the coffee. It’s very important, really. You can perhaps work at home a couple of days a week, but you do need to go in other times; and you need to keep up—which is difficult.

Abbate:

But would you say computing is a good career for women?

Berners-Lee:

Yes, of course it is! Yes, it’s excellent.

Abbate:

Well, thank you very much for talking with me! I think we’re probably at the end. So unless there’s anything else I haven’t hit that you think is important . . .

Berners-Lee:

I can’t think of anything else, no.

Abbate:

Well, thanks very much!

Notes

1. IBM founder Thomas J. Watson was famous for having a sign over his desk that said "THINK."

2. There were two different Mark 1s: the Manchester Mark 1, completed in 1949, which was used by Manchester University; and the Ferranti Mark 1, a commercial version first delivered in 1951. Additional technical details on the Manchester computers can be found in R. B. E. Napper, “The Manchester Mark 1 Computers,” in The First Computers: History and Architectures, ed. Raúl Rojas and Ulf Hashagen.

3. Bowden, Bertram Vivian, ed. Faster Than Thought: A Symposium on Digital Computing Machines. London: Pitman, 1953.