If you're just scanning, it's not THE Difference Engine, it's a replica:
>"To be clear, the museum's difference engine isn't an original built 160 years ago by Babbage, but rather it is a working model painstakingly designed and assembled in the 1990s. ... The London Science Museum keeps one Babbage Engine on display, but its design team also assembled a second model for a private benefactor who financed the project. That donor, Nathan Myhrvold, a former Microsoft executive, originally loaned his Babbage Engine to the Mountain View Computer History Museum in 2008 with the idea to exhibit it for just six months."
Couldn't be, Babbage never finished it, switched to the Analytical Engine (burning his government funding bridges) and never finished that either.
The subject of the article also isn't the original design, they're the No. 2 design following lessons learned working on the Analytical Engine.
Of note: on top of the two Difference Engines, the Science Museum built the printer which Babbage had designed for the Engine. Babbage had realised that many table errors came from typesetting transcription errors, so the printer was designed to produce stereotype plates, templates for mass-printing with limited room for human error.
Also contrary to what the article seems to say, Myhrvold didn't fund the first DE reconstruction. He commissioned one, and part of that commission was used to build the printer.
I believe sections of the Difference and Analytical engines were built. Not the complete project though.
I wonder if the designs could have been simplified a great deal if he had known of Turing machines or boolean math. A machine based on Turing's original idea, or something like boolfuck, probably wouldn't have too many moving parts, though it would be quite slow. I believe Boole even designed a binary calculator that just used marbles and wood seesaws.
The greatest expense with the Difference engine was the thousands of tiny mechanical parts required.
You seem to know about this, so, related question for you.
Do you think it would have greatly changed history if Babbage had succeeded at creating these mechanical computers? Or were they a vestigial dead end, and simply spreading the knowledge and theory to make them was the real extent of their influence? I'm guessing the latter, but in no way am I sure.
I don't think the machine being unfinishable was an accident of history; I think that's an accurate reflection of the phenomenal expense to create one it would have been. Given that the current techniques were largely good enough, it would have been difficult to recover that value. We are incomprehensibly richer now than society was then, it was almost certainly a great deal easier for us to build 20 years ago than it would have been for Babbage, and it still took 17 years and a lot of "drama" even so. The cost/benefit ratio just hadn't quite gone positive, or at least, not positive enough, yet.
Have you read the book "The Difference Engine" by Gibson and Sterling? (Kind of what kicked off the whole Steampunk genre). Basically a taste of modern society could have been realized many decades earlier.
But the real bummer, is that Edison's lab essentially invented vacuum tubes, but shelved it as Edison didn't see any profit potential in it. Another missed opportunity for earlier computing.
I did read the novel, but that's a work of fiction though whose primary purpose is to be enjoyable to read. I don't think it's particularly useful here.
I think so. The difference engine was a century ahead of it's time, but there wasn't anything in the way to prevent technology from developing earlier.
If it had not only been successful, but caught on, people would have quickly made improvements, invented the idea of Turing machines and general purpose computers, Boolean logic, more efficient gates, etc. You could even have had transistors being invented in the 1800s! Who knows how far it could have gotten.
Most of the early electronic computers didn't change the world, they only prefigured the chances and mechanical computers I think wouldn't have been able to come through (you can't really make a mechanical home computer or smartphone).
On the other hand, they would have provided computing power almost a century before electronic computers, who knows what roads could have been taken that weren't open to us with the power of human computers?
well, scan a bit further, the 'replica' is the only one ever made! :) "... a design never built by Babbage that only existed in his plans and sketches"
I was lucky enough to be involved in a demo of the machine at the museum during a visit just over a year ago. I am based in the UK and was in San Jose visiting our company HQ for a couple of weeks. I went to the museum one weekend and was chatting to the two gentlemen who were due to run the demo; when I told them I'd seen the other machine in the Science Museum in London, they asked if I would discuss the differences (pun not intended) between the two during their presentation.
I was happy to oblige and spent a minute or so explaining how much better the one in Mountain View was because it wasn't behind glass and it could be seen in action.
I went back to the museum during another visit last October and saw the machine again. I guess there's now going to be a void to fill next to the Cray, but even without the Babbage Engine, the museum is really worth a visit.
Yes, while the crowd is large, the demonstration is lengthy so people do mill around the machine. You can get quite close and get pretty much any view of the machine you want while it is in operation.
Also agree; looking at the machine is one thing, but actually seeing it in use, working through calculations, is a little bit breathtaking. There's never been a machine I felt was alive, but watching the difference engine (which is the size of a small locomotive!) move its thousands of parts in one smooth sequence, was stunning.
Not only seeing it. Hearing it is impressive. The various shafts and lever rotating and pushing each other, the main drive rotation changes as its load increases or decreases according to where in the "clock cycle" the machine is, the rhythm of the various pieces clicking, pushing and missing each other...
There's a book that was published about 13 years ago by the man leading the program to rebuild the difference engine for London's Science Museum called, "The Difference Engine: Charles Babbage and the Quest to Build the First Computer" [1].
I can't really recommend it, since half (or more) of it is about Doron Swade navigating the politics of a London Museum in order to get the thing built. But there is an interesting history of Babbage.
Ironically a lot of the works on Babbage go into his own trials and tribulations when trying to fundraise his Difference Engine and navigating the politics of 19th Century British Government affairs.
Jacquard's Web [1] was a good break from this tradition and goes into the technical foundations for Babbage's work - highlighting the loom industry in Lyons but primarily focusing on Babbage and Lovelace's technical efforts.
My two favorite quotes from this book:
Babbage does not himself use the words 'programming' or
'program'. These terms had not yet entered the language and
he is therefore obliged to resort to more obscure
expressions. For example, he describes the Analytical
Engine as being made 'special' for the mathematical
formula in question. In precisely the same way, we could
visualize a Jacquard loom that was programmed to weave a
lily as being made 'special' for the task of lily-weaving.
And:
Babbage also borrowed from the Jacquard loom the plan of
creating what he describes as a 'library' of cards that
carry out different functions, with the Analytical Engine's
operator being able to take cards from the library as
required and input them into the machine in order to make it
special for the task. The enormous advantage of the Jacquard
loom was, of course, precisely that it was able to weave any
picture or pattern for which a chain of cards had been made.
Weavers would keep these chains of cards in a storeroom
whose function was very much the same as that of the
library–or we might even say software library–which Babbage
was proposing to create.
Leave it to the Brits to invent a computer that leaks oil. (Yes, the difference engine in question has an oil pan, and I would assume needs regular maintenance.)
When I was a kid, my local kids' museum (Mid-America Museum in Hot Springs Arkansas) had a giant mechanical Lego computer that could play Tic Tac Toe.
Unfortunately, the thing had so many moving parts and was so unruly that I never got to see it actually working. It was almost always out of order and eventually was retired.
I remember hearing about Danny Hillis (who went on to co-found Thinking Machines, who produced the massively parallel Connection Machine computers) building a tinkertoy computer. A little bit of digging turned up this book w/ some a chapter that includes, I believe, the computer you're talking about: https://archive.org/stream/tinkertoycomputer00dewd
I was living in Mountain View when they first unveiled this beautiful beast, and went to a couple of the very early exhibitions. I love everything about the Computer History Museum, and recommend it heartily to anyone visiting the area. I've taken a huge variety of guests (from my parents, to non-techie girlfriends, to nerds of many types, etc.), and I think everyone has enjoyed it and learned something. The Babbage engine is one of the coolest things in the building, but having it go away doesn't make the CHM any less worth visiting.
In short: If you haven't seen the darned thing, and you're anywhere near Mountain View, I guess now is the time. And, if you miss the Babbage engine, you should still go check out the CHM. As nerds, it's like the museum of our people. Where else can you see one of the first computer games or hear one the first computer music pieces being demonstrated by the people who wrote them? (Though those also have a time limit...the folks who wrote those first games and musical compositions are in their seventies; they won't be docents at the CHM forever.)
I wonder if it would have been possible to build a Difference Engine/Analytical Engine equivalent machine during the same era using electrical relays. According to Wikipedia the first relays were invented in the 1830s or 1840s for use in telegraphs. It may have been many decades before relays were reliable enough or cheap enough to make such an undertaking practical, though.
Wolfram (1) points out that Babbage and Lovelace knew Charles Wheatstone - whose telegraphy work should have presented obvious electromechanical opportunities if Babbage had been able to actually finish anything, and perhaps if Lovelace had lived longer.
>The Mountain View Computer History Museum is saying goodbye to one of its most unique exhibits, if not also its most priceless.
I know its poor form to mention such things but "unique" and "priceless" are both absolutes: something is unique/priceless or it's not. For example, if one thinks about two unique things it is not possible to say which is more unique than the other. (If one thinks about Difference Engines, since there is one in the Science Museum and one in the Computer History Museum, neither is unique.)
Usually when I see this sort of thing I shrug and remind myself that living languages constantly change. (It seems that "unique" has lost some of its force and is changing its meaning to something like "very unusual" or "very rare".) But two examples in one sentence apparently stirs the old fuddy-duddy in me to action...
perhaps it's the domain people refer to? For example:
A chair that I make is unique, there is not another exactly like it.
A chair that I make is unique, there is only one in the world made by me.
In this case, the chair is unique in a very specific way.
However, the Babbage engine is unique in more ways. First mechanical computer of a certain complexity. Only mechanical computer with so much funding from the government. Build quality, ability etc...
Would it be possible to rebuild one using 3d printed parts (probably laser sintered metal would be the best)... And then, build an analytical engine... And then make the analytical engine drive a 3d printer...
As the difference engine computes result of polynomial equations (upto x to the power 7, if I remember the demo correctly) , I don't think its turing complete enough to drive a 3d-printer completely. It can, perhaps, drive the generative design of a 3d printed art based on the result of a polynomial equation.
There's a project to build the Analytical Engine also, http://plan28.org/ some great videos about how it works there, finally feel like I understand it.
I have been at computer history museum recently and got a chance to see the Babbage machine. It is marvellous and within seconds, you will relish its beauty. It lets you realise how the computers has changed over the years.
Now that you mentioned it, the printer directly prints the decimal number in the accumulator, so it's unlikely it could print lyrics.
We could, however, build a music-box-like device that would "print" the accumulator as pair of pitch/duration notes, a "sound impression device", or SID.
That would certainly drive future historians nuts.
"Modern manufacturing methods were used but uncompromising care was taken to ensure that the precision achievable by Babbage was nowhere exceeded." [1]
Besides that, the parts will be stressed with a lot of force. I doubt whether plastics are strong enough. Look at it working: https://www.youtube.com/watch?v=jiRgdaknJCg (at about 2:30 it is just computational art :)
I can't believe the CHM is located smack in the middle of Silicon Valley and nobody is willing to put their hand in their pocket to keep this available as an educational resource to inspire future generations. Pathetic.
This isn't a money issue. Nathan Myhrvold commissioned the machine to live in his house. After loaning it to the Computer History Museum for longer than originally planned, he's taking it for private display (as originally intended).
He's worth $650m plus, so there's likely no amount of money that would convince him to leave the machine in the museum.
>"To be clear, the museum's difference engine isn't an original built 160 years ago by Babbage, but rather it is a working model painstakingly designed and assembled in the 1990s. ... The London Science Museum keeps one Babbage Engine on display, but its design team also assembled a second model for a private benefactor who financed the project. That donor, Nathan Myhrvold, a former Microsoft executive, originally loaned his Babbage Engine to the Mountain View Computer History Museum in 2008 with the idea to exhibit it for just six months."