So I want you to picture the classic archetype
of the mad professor. You know, the exact image,
I mean. Right. The wild hair, maybe a bit of
a frantic energy. Yeah, exactly. That kinetic
energy that makes them kind of hard to keep up
with. They're usually holding some strange contraption
that looks like it might explode in a shower
of sparks. And everyone around them just calls
them Doc. Yes. It's a trope we see in movies
constantly, right? From Back to the Future to,
well, those old black and white monster movies.
It's the standard shorthand for the genius who
is too busy thinking about the secrets of the
universe to worry about social norms. Or combing
their hair. Exactly. But what if I told you that
this exact character actually existed? And not
only did he exist, but he was a calm, critical
force behind winning World War II. And perhaps
even more surprisingly, he is the reason machines
can read your handwriting today. It's just wild.
Today on The Deep Dive, we are unpacking the
life and work of Alan William Mark Coombs, known
to his colleagues, and soon to you, simply as
Doc. And to guide us through this, we've pulled
together a stack of biographical records, some
Wikipedia entries regarding his work at the Post
Office Research Station. Which is way more exciting
than it sounds, I promise. It really is. And
we're also looking at historical accounts of
the Colossus computer. So the mission today isn't
just to talk about a guy who built a computer.
We aren't just, you know, listing out specs and
dates. No, the goal is to move Alan Coombs out
of the shadows. He often gets listed as a footnote
next to bigger names like Alan Turing or Tommy
Flowers. Right. But we want to explore the bridge
Coombs built. He is the missing link between
wartime code breaking and the modern automation
of information. We're connecting the high stakes
world of cracking the Enigma and Lorenz ciphers
to the everyday miracle of a machine reading
a postcode on a letter. Which is a crazy trajectory
when you think about it, from saving the free
world to sorting the mail. Yeah. So let's get
into it. Let's meet the doc. Let's do it. We
have to start with the stats just to kind of
ground us in reality here. Alan Coombs, born
in Bristol, England in 1911. And looking at his
early life, you see immediately that he didn't
just stumble into engineering as a hobby. He
was an academic heavyweight from the very beginning.
He went to the University of Glasgow, getting
his Bachelor of Science in 1932. But he didn't
stop there. He went on to earn a Ph .D. in 1936.
Can we just pause on that for a second? A Ph
.D. in the 1930s? That feels pretty significant.
Oh, it was incredibly rare compared to today.
In the 30s, engineering was often viewed as a
practical trade. You learned by... doing, you
know, by apprenticing. Right. Getting your hands
dirty. Exactly. To have a doctorate in it meant
you were operating at a theoretical level that
most people just didn't touch. You were dealing
with the physics of electricity, the deep math
of signal processing, not just soldering wires.
Right. And he wasn't done accumulating letters
after his name either. No. In that same year,
1932, he also received an ARTC award, which was
later designated as the ARCST from the University
of Strathclyde. So by the time he is 25 years
old, he is highly credentialed. He understands
the math, the physics, and the mechanics. He's
a double threat. But here is the contrast that
I love, and it's what makes him such a great
character to dive into. Despite all those degrees,
despite being one of the smartest guys in any
room, nobody called him Dr. Coombs or Professor.
No, he was universally known as Doc. Doc. It's
affectionate, isn't it? Yeah. But it also implies
a certain kind of personality. It does. And the
descriptions of him are so vivid. He wasn't your
stiff academic in a tweed suit. He had this notable
facial tick. Yeah. And looking at the source
material, there was a really interesting note
on this. The biographers mentioned that today
this behavior would likely be classed under Tourette's
syndrome. But back in the 30s and 40s, they didn't
really have that diagnosis handy, or at least
it wasn't socially understood in the same way.
Exactly. So to his colleagues, it just became
part of the package. Combined with his intellect
and his intense, rapid -fire way of speaking,
it just contributed to this mad professor vibe.
It wasn't seen as a disability. It was seen as
a quirk of high intelligence. It makes him feel
so real to me. You can just imagine him in the
lab, maybe twitching slightly, mind racing a
mile a minute, holding a soldering iron and muttering
about voltage. And I think acknowledging that
persona adds a really vital layer of humanity
to the machines we are going to talk about. We
often think of the people at Bletchley Park or
Dollis Hill as these stoic robotic figures. The
stiff upper lip. Right. But here you have Doc
with his tics and his brilliance leading a team.
It suggests that the intense discipline required
for his work was balanced by a very distinct,
very human personality. It disrupts the idea
that you have to be boring to be brilliant. Terrifically
said. So we have the man. Now let's put him in
the history books. We are moving the timeline
to World War II, and we have to talk about his
workplace, the post office research station at
Dulles Hill. Now, if you're not British, post
office research station sounds like a place where
they, I don't know, test envelope glue or...
Design new stamps. It sounds incredibly mundane,
I know. But Dulles Hill was essentially the British
equivalent of Bell Labs or a secret DARPA facility
today. It was a hub of high -level electronics
work. Because the post office ran the telephone
network. Exactly. So they had the best experts
on valves, vacuum tubes, and signal processing
in the entire country. If you wanted to build
something electronic in the 1940s, this is where
you went. And this brings us to the big one,
the Colossus computer. Specifically, the Mark
II. Now, this is a crucial distinction we need
to make. Usually when you hear about Colossus,
you hear the name Tommy Flowers. He designed
the original Colossus, the Mark I. Which was
the world's first programmable electronic digital
computer. It was. But the Mark lie was essentially
the prototype. It was the proof of concept. It
proved you could use thousands of vacuum tubes
to process data without them all burning out
instantly. Which, by the way, was the prevailing
wisdom at the time. People thought it couldn't
be done. But Coombs comes in for the Mark II.
Yes. Coombs was a principal designer of the Mark
II, which was the production version of the machine
used at Bletchley Park for code breaking. What
was the difference? Was it just a software update?
Oh, no. It was a massive hardware leap. The Mark
I had about 1 ,600 valves. The Mark II, which
Coombs helped engineer and eventually took charge
of, had 2 ,400 valves. It was five times faster
than the original. We are talking about a machine
that could read paper tape at 5 ,000 characters
per second. 5 ,000 characters per second in 1944.
That is just mind -boggling. To give you a physical
sense of that, the tape was moving so fast, about
30 miles per hour, that the edges of the paper
tape acted like a saw. If the tape broke and
hit you, it would cut you open. Okay, that is
actually terrifying. It was a beast of a machine.
It generated so much heat from those 2400 valves
that people worked in their undershirts even
in the dead of winter. And here is the pivot
point in the story. Tommy Flowers, the visionary
behind the concept, moved on to other projects.
He left the Colossus work. He did. He left to
focus on other things. And who took over leadership
of the project? Docums. He became the guy keeping
these massive heat generating machines running.
And remember, they weren't just building one.
They were trying to build a fleet of them to
defeat Nazi encryption before D -Day. I want
to pause on the why here. We throw around terms
like Nazi encryption. Yeah. What were they actually
trying to do? Because most people know the Enigma
story, thanks to all the movies. Was this Enigma?
No, and that's a very common misconception. Enigma
was used for tactical stuff, tanks talking to
submarines, that sort of thing. Coombs and Colossus
were attacking the Lorenz Cipher. Which was different.
It was even more complex than Enigma. The Lorenz
was used for high -level communication between
Hitler and his top generals. It used 12 different
wheels to scramble the message. And Colossus
didn't read the message directly. It used statistical
analysis to find the starting positions of those
wheels. It was essentially looking for patterns
in the noise. So Coombs is managing a team that
is building these massive electronic brains to
hunt for statistical patterns in German radio
signals. Precisely. And if they got it right,
the Allies knew exactly what Hitler was planning
before his own generals did. I want to capture
the atmosphere of that time because Coombs actually
wrote about this later on. And the quote he gave,
it gives me chills every time I read it. He said,
no member of our team could ever forget the fellowship,
the sense of purpose and above all. The breathless
excitement of those days. Breathless excitement.
It's so evocative, isn't it? Usually war stories
are about grim determination or fear or just
doing your duty. It really is unique. You have
to remember, this was a secret bunker, essentially.
They were working on technology that didn't officially
exist. If they failed, convoys sank. If they
failed, the invasion of Europe might fail. And
yet he calls it breathless excitement. It sounds
like the thrill of discovery. Like they knew
they were building the future, even if they couldn't
tell anyone about it. That is the key. They were
inventing the digital age in the dark. They were
solving problems no human had ever faced before,
like how to synchronize 2000 electronic switches
perfectly. The fellowship he mentions, that camaraderie,
must have been incredibly tight. They were the
only people on earth who understood what they
were doing. And that secrecy, that is the double
-edged sword of this whole story, because that
secrecy didn't end when the war did. No. In fact,
it got tighter. Winston Churchill ordered the
Colossus machines to be dismantled, destroyed.
That hurts to hear, just smashing up history.
It was the dawn of the Cold War. He wanted to
keep the fact that the British could read these
codes a secret from the Soviets, who were using
similar technology. So for decades, the work
Coombs and his team did was classified, top secret.
Imagine building the first computer. Literally
changing the course of human history. And not
being able to tell anyone for 30 years. Not your
wife. Not your kids. It is almost unimaginable
today where we post our achievements instantly.
But that was the reality. Coombs went back to
work and the world went on thinking the Americans
invented the computer with Enon S in 1946. But
Coombs knew better. He knew. But he kept his
oath. This silence lasted until 1976. Enter Professor
Brian Randell. This is the big turning point.
Right. So jump forward to the mid 70s. Brian
Randall is a computer scientist researching the
history of the field. And he keeps hearing whispers,
rumors about a British machine. He starts digging
around because he's prepping for a conference
at the Los Alamos National Laboratory in New
Mexico. The home of the atomic bomb. Kind of
a fitting place for revealing massive government
secrets. Exactly. And he manages to get something
incredible. the British government finally decides
to loosen the grip. Just a little bit. Just a
crack. In late 1975, they release a series of
captioned photographs from the public record
office, and Randall obtained permission to present
a paper on the wartime development of the colossi
at the post office research station. So picture
the scene. It's 1976, Los Alamos. A room full
of top -tier scientists and historians. Randall
presents this paper. And the room just explodes.
It was a total rock star moment for engineers.
You have to understand, these people thought
they knew the history of their field inside and
out. Suddenly, Randell is standing there saying,
no, actually, there was a programmable electronic
computer two years before ENIAC. The interest
was so high that they actually had to organize
a special evening meeting just to handle all
the questions. And guess who was there to answer
them? Doc Coombs and Brian Randell. That has
to be one of the most satisfying moments. I would
imagine so, standing there, finally able to say,
yes, we did this. Yes, it worked. Randall later
published an article called The First Electronic
Computer. This was the moment the history books
were fundamentally rewritten. And Coombs was
finally able to bask in that revelation. After
30 years of holding his tongue, he could finally
explain what that breathless excitement was all
about. It's a powerful validation for him. But
what I find even more interesting, and this is
where this deep dive really gets into the weeds,
is that Coombs didn't just retire after the war.
He didn't just sit around waiting for the Secrecy
Act to expire. No, he kept building. And this
is where the story gets really surprising for
me. We go from cracking Nazi codes to sorting
the mail. It sounds like a massive downgrade,
doesn't it? Like going from being James Bond
to working at the DMV. It really does. Yeah.
Why did he make that shift? Well, because technologically
it was actually a massive leap forward. OK, let's
unpack that. The war ends. Coombs is still at
Dulles Hill. First, he worked on something called
the Amosaic Computer. It stands for Ministry
of Supply Automatic Integrator and Computer.
It's a bit of a neglected fragment of history,
but it was mainly used for calculating radar
data and aircraft trajectories. So it shows he
stayed on the cutting edge of pure computing.
But then comes the big shift. Yes. He takes over
the scientific side of R -14. R -14. Sounds like
a droid from Star Wars. It was the division working
on postal mechanization. Specifically, optical
character recognition, or OCR. Okay, so the problem
is people write addresses on envelopes, and sorting
them by hand is just way too slow. Precisely.
The post office was drowning in mail. They desperately
needed a machine to read the envelope and sort
it into the right bin automatically. Which honestly
sounds harder than cracking Enigma. Have you
seen some people's handwriting? Oh, absolutely.
My doctor's handwriting is basically encryption.
It is exponentially more difficult in many ways,
and that is the connection here. If you think
about it, Coombs went from looking for patterns
in encrypted data, identifying the statistical
anomalies in the Lurin cipher, to looking for
patterns in human squiggles on an envelope. Oh,
wow. It's all pattern recognition. Exactly. In
crypto, the noise is the encryption algorithm
hiding the message. In OCR, the noise is the
messy ink, the bad handwriting, the coffee stain
on the envelope. Coombs had to figure out how
to teach. machine to look at a squiggle and say,
that is statistically likely to be the letter
A. And he's doing this in the 1950s. There are
no neural networks, no AI as we know it today.
No cloud computing, just hardwired logic and
analog circuits. He moved to the new BT Research
Center at Martlesham in Suffolk and led the work
that resulted in early postcode reading machines.
He had to figure out how to interpret lines and
curves electronically. So every time a machine
automatically sorts my mail today, or I scan
a document on my phone and it magically turns
into text, I can trace a little bit of that back
to Doc Coombs. You certainly can. He pioneered
the theory of how computers interact with the
messy, unstructured real world. He moved computing
from calculation, just adding numbers to perception.
And he wasn't just building these things in a
dark room. He was teaching people how they worked.
Which brings us to the flash gun and the caltrop.
Yes. Coombs was a frequent lecturer, and true
to his doc persona, he was not boring. He wanted
people to understand how we see so we could understand
how machines might see. I really wish I had a
professor like this. Describe his favorite trick
for us. So he wanted to demonstrate feature detection
in the human visual system. To do this, he would
use a flash gun. basically a high intensity strobe
light like you'd see on an old camera, but much,
much more powerful. I can see the mad professor
vibes returning in full force. Oh, yeah. He would
darken the room, flash this intense light. And
because of the persistence of vision in the human
eye, the way an image lingers on your retina
for a split second, the audience would literally
see a character like a letter or a shape disintegrate
fragment by fragment. That is so cool. So he's
breaking down vision into bits. He was proving
that our eyes don't. take a static photo, they
process features, lines, curves, angles. And
he used this to explain a concept he called the
caltrop. The caltrop? Like the spiky weapon you
throw on the ground to pop tires? Yes. The shape
is the key there. A caltrop has four points.
No matter how you drop it, one point is always
sticking up. Coombs used this physical object
to explain multidimensional space. Okay, you're
going to have to explain that to me like I'm
five. Because multidimensional space sounds like
pure science fiction. Fair enough. Imagine every
letter isn't just a picture, but a collection
of scores. A score for curviness, a score for
straight lines, a score for holes in the shape.
If you map those scores in a 3D graph, All the
A's cluster in one area and all the B's cluster
in another area. It's about mapping features
in space. So he was trying to teach people that
machines could see by converting shapes into
math. Exactly. He was deconstructing vision to
reconstruct it digitally. He's trying to get
people to visualize what we now call a feature
space, which is totally fundamental to how modern
AI works. It's amazing to think about him standing
in front of a chalkboard, flashing lights, twitching
with excitement, trying to explain to a room
of confused people how a machine could learn
to see. And doing it decades before computer
vision became a buzzword in Silicon Valley, he
was laying the theoretical groundwork for everything
from facial recognition to self -driving cars.
So what does this all mean for us? We've gone
from a Ph .D. in Glasgow to the high -stakes
secrecy of Bletchley Park to the flashing lights
of lecture halls and automated mail sorters.
Sadly, Alan Coombs passed away on January 30th,
1995 in Yelton, Devon. He was 83 years old. But
he left quite a mark on the world. He represents
the unsung technical brilliance that underpins
our modern life. We love the stories of the lone
genius, the Turing, the Einstein, but Coombs
was the guy who made things work. He didn't just
build the hardware with Colossus. He pioneered
the theory of pattern recognition. He bridged
the gap between a machine that calculates numbers
and a machine that actually understands the world
around it. Exactly. Without that bridge, without
his work on OCR and pattern recognition, our
digital world would look very, very different.
He helped computers open their eyes. I want to
leave you with a thought to mull over. We often
think of computer vision or AI reading text as
a modern invention, something from the last 10
or 20 years. But consider Doc Coombs in that
bunker in 1944, or in his lab in the 50s. It
raises a fascinating question. Was that breathless
excitement he felt just about winning the war?
Or did he already see a future where machines
could read, see, and understand us? Maybe the
mad professor wasn't mad at all. Maybe he just
saw the future before the rest of us did. I think
he certainly did. Thanks for listening to this
deep dive into the life of Alan Coombs. It's
been a pleasure. See you next time.