Interviewith grace Murray Hopper interviewers: Beth Luebert, Henny Tropp date of interview: 5 July 1972 place of interview: nm

Computer Oral History Collection, 1969-1973, 1977 

21

 

Grace Murray Hopper Interview, July 5, 1972, Archives Center, National Museum of American History 

 

 

HOPPER: 

He could tell you lots about him. He lived right next door to the Laboratory in one of 

those temporary housing units the Army built. He can tell you lots about all of this. 

Particularly about how the other machines, about how Mark III got started. Morris 

(Rubinoff?) was his name, a Professor at (Moore?) School. 

TROPP: 

That's somebody perhaps that you and I ought to see together. 

HOPPER: 

You must talk to him long and plenty. He was right in the thick of all of it. Particularly in 

the development of the early drums. We had disks that we worked with first, then the 

early circuits and building the drums down at the ship yard and so on. 

I can remember when Aiken got the, well he had them, I knew about it, it wasn't practical 

yet for Mark III, he had four of the big square magnets which were the beginning of the 

core memories and they were shipped from Germany.. 

I don't know who, the Army, Navy or who had found them during the fall of Germany, 

but they were shipped over to the Laboratory, very special. 

There were four, three of them in that box and they were being unpacked. They were 

squares about this big, the beginnings of all the core memories. 

Other people claim them now, but I know personally they were the first cores to appear in 

this Country. 

TROPP: 

That would have been late '45 or early '46? 

HOPPER: 

'45. Some time in '45. No, wait a minute, early '46 I guess. 

TROPP: 

Early '46. 

HOPPER: 

For additional information, contact the Archives Center at 202.633.3270 or [e-mail]

 

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Computer Oral History Collection, 1969-1973, 1977 

22

 

Grace Murray Hopper Interview, July 5, 1972, Archives Center, National Museum of American History 

 

 

They were shipped in a very special wooden box and they had been found in Germany, 

but we could not use them for Mark III because they didn't know enough about how to 

use them. 

But I can remember having them downstairs in the Laboratory and building these 

(                         ?) for them and everything and working on the concept of the magnetic 

core memory. 

Now (Rubinoff?) can tell you more about that but I can remember being there when 

Aiken unpacked those cores, they were the first ones we ever saw. That's the size they 

were then. 

TROPP: 

I guess, you know one of the things that have become clear in talking to you, listening to 

you and talking to other people, is that you were working, as you indicate, with a long 

tunnel ahead of you with these problems to solve. Very little intercommunication and 

very little outside communication so that you were not involved in outside developments. 

You have these tremendous goals and… 

HOPPER: 

Our minds were full of what we were doing. You remember Mark I stopped very quickly 

when we couldn't find out what the bugs were. When you have to find the bugs in a 

machine, they used to borrow regularly. 

I had a mirror, something like this one which came with my handbags. This is a later one, 

but I always had a small mirror about this big and one way to find the bugs in Mark I was 

that they were very often caused by the fraying of the brushes on the counters in which 

case they would spark. 

So they would turn out all the lights and then they would borrow my mirror and they 

would go along and run it and they would look for the sparks in the counters and the 

mirror would pick up the sparks you see. Because otherwise you couldn't see down in to 

find the sparks. They used my mirror for it all the time. Because I always had it in my 

handbag, it came with the handbag. 

TROPP: 

Well Beth, it's really incredible when you look at the early developments as to how few 

people accomplished so much.  Now you have teams twice that size working on one little 

biddy thing. (LAUGHTER). 

HOPPER: 

For additional information, contact the Archives Center at 202.633.3270 or [e-mail]

 

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Computer Oral History Collection, 1969-1973, 1977 

23

 

Grace Murray Hopper Interview, July 5, 1972, Archives Center, National Museum of American History 

 

 

Well in the past five years, starting from the time I returned to active duty on 1 August 

'67, the most I've ever had in my group is seven people and will have completely coped 

with the standardization of cobalt and finally got the letters that went out from the 

National Bureau of Standards on the 29th June delegating it to the Navy.  The whole 

development of the first pieces of (                                                         ?) to insure that the 

compiler did in fact need a (stimulator?). We've never had more than seven people. Even 

when (                                               ?) that's all there has ever been. You can still get 

more (                                 ?).  The more paper you put on the more communication lines 

you set up and (                                   ?). 

TROPP: 

In talking to John Backus about the development of FORTRAN, that was a group of 

about eight. 

HOPPER: 

That's right. And the first compiler that (          ?) I wrote myself by hand, every 

instruction. 

TROPP: 

Which is still the most efficient way when you can do it. (LAUGHTER). 

Again, I seem to be getting away from your questions Beth. 

LUEBBERT: 

Perhaps really the last question I was looking at was how was Aiken like as a person to 

work for? 

HOPPER: 

You could make any mistake in the World once. If you made the same mistake twice, 

heaven help you. 

TROPP: 

That sounds exactly like Commander Hopper's spearing. (LAUGHTER). 

HOPPER: 

I adopted that line. I used to argue with Dick Bloch because he was always getting in 

trouble. And I would try to explain to Dick that he's just exactly like a computer, he's 

wired a certain way. And Dick would say, well its right to do this. And I'd say, I don't 

For additional information, contact the Archives Center at 202.633.3270 or [e-mail]

 

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