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The Greatest Machine Never Built
mikejuk writes "John Graham-Cumming is the leading light behind a project to actually build the analytical engine dreamed of by Charles Babbage. There is a tendency to think that everything that Babbage thought up was little more than a calculating machine, but as the video makes 100% clear the analytical engine was a real computer that could run programs. From the article: 'Of course Ada Lovelace was the first programmer, but more importantly her work with Babbage took the analytical engine from the realms of mathematical table construction into the wider world of non-mathematical programming. Her notes indicate that had the machine been built there is no question that it would have been exploited just as we use silicon-based machines today.
To see the machine built and running programs would be the final proof that Babbage really did invent the general purpose computer in the age of the steam engine.'"
There is a tendency to think that everything that Babbage thought up was little more than a calculating machine
By whom? I have never heard the analytical engine described in terms like that.
You're probably thinking of the Difference Engine that the London Science Museum built in 1991 (output mechanism added in 2000). Afaik nobody's constructed an Analytical Engine, which is considerably more complex to build.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
But now we can build computers within computer programs with redstone. Babbage never had redstone.
It was one machine... many others like it were being built. This one caught traction because the media/historic writing was on it's side.
What? Who else was designing a turing complete computer in the 1830s? I haven't heard of them.
"First they came for the slanderers and i said nothing."
A lot happened in the first part of the Victorian era in the UK - I am referencing the UK because (a) that's where Babbage was and (b) I know a little of the history. This was a period when blacksmith engineering was rapidly giving way to scientific engineering. In essence, just as now with silicon, engineering techniques were developing fast as a response to new requirements for precision and metallurgy. So "the technology of the time" would itself have been different if the Government of the day had grasped just what it had, and made a real push for it. I would go out on a limb and suggest that if Prince Albert hadn't died when he did, the Analytical Engine would probably have been built. He was a major proponent of technical development and ruffled a lot of Establishment (classically educated) figures, but his Great Exhibition was a huge success. He died in 1861, in his early 40s. Babbage in 1871.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
A nice "what if" novel was written by Gibson and Sterling, based on a posited successful adoption of the difference engine in Victorian times. It's classed as Sci Fi, but is more of a novel set in an alternative history. Definitely worth reading.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
That is because Samuel William Jefferson, who invented the computer and build one, also invented the time machine in 1827.
In 2079 his great-great-great-great-grandson, Hydro Jefferson, had an argument with his girlfriend about a cupcake (or a dancer called C-Cups. The books are unsure about that.)
She then went back in time and killed S.W. Jefferson as a little baby.
Don't fight for your country, if your country does not fight for you.
Charles Babbage is the ultimate example of "The perfect is the enemy of the good." He was so caught up in what he could do better with the Analytical Engine that he did not fill the orders for the Difference Engine. If he had set some people up making Difference Engines rather than spending the money he was given to build a Difference Engine to design the Analytical Engine, he might have been able to get a steady enough flow of money to fund building and designing variations on the Analytical Engine. The question of course is, if he had done that, would he have lived long enough to get any work done on the Analytical Engine at all?
The truth is that all men having power ought to be mistrusted. James Madison
To expand: the Difference Engine is a digital computer, but it's a special purpose one, like a simple calculator, except made out of gears and cogs. It can do certain mathematical calculations which had previously been laborious and error-prone. The government wanted a Difference Engine to make tables for indirect fire with guns, these tables (previously calculated by hand), allow you to hit things far away on the first shot if you know how far away exactly they are. The Difference Engine's promise was fulfilled actually just a few decades or so after it had been conceived, mechanical computers became quite widespread and only died out when the transistor made them uneconomic in the late 20th century.
The Analytical Engine is a general purpose computer. It can work on any computable problem. Nobody ever built anything like that, the first general purpose computers were electronic.
Can you really say someone "invented" something if they never actually managed to build it? I have tremendous respect for the work Babbage and Lovelace did, but honestly, I'm not sure they invented the computer any more than da Vinci invented the airplane.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
John Graham-Cumming is the leading light behind a project...
Leading lights generally work better in front of things. I think your metaphorator might be a bit misaligned...
Yep. Looks like you've got some sinusoidal co-pleneration between the literal input shafts. Gonna have to replace your main spurving bearing, maybe the secondary too. A couple of the marzel vanes on your imagery agitator are looking a pretty worn, might want to get those replaced while you're at it.
Bugrit! Millenium hand and shrimp!
Or, to simplify; the difference engine is a caclulator, and one has been built. The analytical engine is a turing-complete computer, and one has not been built.
Python: 'And then suddenly you have a language which says "we're all stuck with whatever the whiniest coder wants".'
It's a great project, but I don't think it's really happening. The guy behind it is into PR, not cutting metal. "The project hopes to have a working machine before the 2030s."
There's a simulator for the Analytical Engine. It runs in a Java applet, and you can write and run programs. It's not that hard to program. The Analytical Engine is comparable to a low-end programmable calculator, without trig functions.
The machine itself isn't that complicated; just big. It's big because Babbage specified 1000 memory locations of 50 decimal digits each. So you need 50,000 memory wheels. That's all for data; programs are on cards. The "mill" part of the machine is roughly the complexity of a good mechanical desk calculator.
That's actually far too much memory for what the thing can do. Nobody seems to know why 50 digits, either. Babbage had figured out shifting, and understood scale factors, so it's not that he wanted to put the decimal point in some fixed place and work in fixed fractional mode.
If the thing were built with 100 memory locations of 10 digits each (a typical configuration for an 1980s programmable calculator), it would be equally capable, and 1/50th the size. That's enough capacity for navigational tables and astronomy. Built with full memory, it would be the size of a locomotive, and most of the memory would be idle. The extra memory wouldn't make it useful for bookkeeping or business; the I/O isn't there for that.
I wrote in and asked how many part numbers (different parts) the machine has, which gives a sense of how much manufacturing effort is required. There probably aren't that many; all 50,000 memory wheels will be identical, and most of the "mill" is repeats of a 1 digit mechanical adder. I didn't get an answer.
Somebody should model the machine in SolidWorks or Autodesk Inventor. (Or upgrade the mechanism support in Minecraft and let that crowd do it.)
The problem is that Babbage didn't actually have any "computing babies" -- his computing genotype died out, and a new computer bloodline evolved years later. Turing was part of that family tree.
Sorry for the mildly mixed metaphor.
Got them moderator blues I blieve I walk out the do', With these mod-points I been gettin', I 'most never post no mo'
I think I'll take my chances with Government and taxes versus Libertarians and giant corporations, thank you. I can at least vote for Governments and pay an accountant to ensure I don't pay too much tax. But in your world, where the price of food and oil is set by whoever can buy up all of it and dole it out at will, I don't have a vote.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Thomas Fowler actually built a calculation machine in wood, presented to the Royal Society in 1840!!!!
http://www.thomasfowler.org.uk/
This only fault was not to have the social background that Babbage had...
I quote from the front page of the site dedicated to him:
Fowler writes to Airy:
"I had the honor in May 1840 to submit the machine to the inspection of many Learned Men in London among whom were the Marquis of Northampton, Mr Babbage, W F Baily and A de Morgan Esq with many other Noblemen and Gentlemen, Fellows of the Royal Society etc and it would have been a great satisfaction to me if I could have had the advantage of your opinion also. They all spoke favourably of my invention but my greatest wish was to have had a thorough investigation of the whole principle of the machine and its details, as far as I could explain them, in a way very different from a popular exhibition:- this investigation I hope it will still have by some first rate men of science before it is be laid aside or adopted.
I am fully aware of tendency to overrate one's own inventions and to attach undue importance to subjects that preoccupy the mind but I venture to say and hope to be fully appreciated by a Gentleman of your scientific achievements, that I am often astonished at the beautiful aspect of a calculation entirely mechanical.
I often reflect that had the Ternary instead of the binary Notation been adopted in the Infancy of Society, machines something like the present would long ere this have been common, as the transition from mental to mechanical calculation would have been so very obvious and simple.
I am very sorry I cannot furnish you with any drawings of the Machine, but I hope I shall be able to exhibit it before the British Association at Devonport in August next, where I venture to hope and believe I may again be favoured with your invaluable assistance to bring it into notice. I have led a very retired life in this town without the advantages of any hints or assistance from any one and I should be lost amidst the crowd of learned and distinguished persons assembled at the meeting without some kind friend to take me by the hand and protect me."
Charles Babbage, Augustus De Morgan, George Airy and many other leading mathematicians of the day witnessed his machine in operation. These names have become beacons in the history of science yet nowhere will you find reference to Thomas Fowler. Airy asked that he produce plans of his machine but Fowler, recalling his experience with the Thermosiphon, refused to publish his design.
The machine was superior in many respects to Babbage's calculating machine, the Difference Engine, generally regarded as the first digital computer. Fowler's machine anticipated the modern computer in its design by using a ternary calculating method. This is in contrast to Babbage's machine which performed a decimal calculation, an approach which made his machine very complicated. The government of the day became increasingly disillusioned by the money they were having to pour into its development. So much so that the government refused to even look at Fowler's machine. Had Thomas Fowler published his design he would no doubt have won the support of many leading mathematicians of the time. Unfortunately, it took several decades before his approach was re-invented and in the mean time his name had slipped into obscurity.
Yes, there is a need to describe a device as Turing complete if you are going to be accurate. The parent post above got it dead right when he said that Konrad Zuse didn't even get the right millennium in terms of when the first (known) mechanical computer was built. That would likely be the Antikythera mechanism, and there is reason to believe there were machines of similar complexity which existed earlier. The Egyptians and Babylonians had clockworks which predated even this device by several millennia, and depending on your definition you could even describe things like Stonehenge to be a computer.
The point of suggesting Turing completeness is that you get into the realm of programmable computers that have a set of characteristics all to themselves... and that Alan Turing described mathematically a set of characteristics that distinguishes these early mechanical computers (not merely calculating devices either) from more modern computational machines that are typically called "computers" in a modern context.
The issue with Konrad Zuse is that he did build the first functioning Turing complete device (well... made a strong attempt at it with the Z1), with other computers being built about the same time.
The amazing thing about the Babbage design is that it was using technology of a much earlier era and still could get the job done. That is why it is an amazing design and why so many "what if" statements keep getting made about it. Britain certainly had accurate tables for performing firing solutions with their weapons, but just imaging what World War I would have been like with a United Kingdom having at its disposal nearly a half century of computer technology experience is certainly something that would have changed the outcomes of war. Or perhaps if like many inventions the Germans took designs and ideas from the British and refined them to a much larger degree... imagine what Imperial Germany could have done with the same machine and subsequent designs incorporating the electrical circuits that existed in the early 20th Century.
Assuming the best of all possible worlds, the Analytical Engine is built and it works, what aspects of life would have been advanced by it? Whenever I hear about it, people talk about it as if it would have turned Victorian London into a Steampunk Silicon Valley and enabled great advances.
Would running programs on the difference engine have been sophisticated enough or capable of enough complexity to solve significant engineering problems that were too difficult or time consuming to solve with the by-hand mathematics of the era?
Was the system scalable enough that you could have built a bigger one capable of handing more useful/larger computations? Or shrinkable enough to make portable to use on ships or in remote locations, yet still calculate useful things?
That's true.