OT Babbages Difference Engine - Bare Metal Computing !

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Best regards, Spehro Pefhany

There is another one in the Science Museum in London. They made two and gave the second one to the sponsor who funded the project. He works for Microsoft.

Leon

I saw them working on this when I visited the Computer History Museum the other month. Very cool. A couple of my photos and a video of the engineers testing it:

Also, for those interested in such things, Charles Babbage's actual preserved brain is (or was) on display at the Natural History Museum in London.

Dave.

Ah yes, correction to my other post, Babbage's brain was on display in the Science Museum in London, not the Natural History. The Difference Engine in London wasn't working when I was last there, but still damn impressive to look at.

Dave.

I was under the impression that Babbage's design was manufacturable with the then current technology - the story from the London Science Museum was that they had built their version of the machine using late nineteenth century technology.

Babbage's problem was that making and fitting together all the parts was a big and expensive job - he didn't have the right kind of personality to raise the money or run a big enough workshop to do the job in a manageable time, and in fact tended to get into conflicts with the machinists who did work for him.

The Wikipedia article doesn't conflict with any information I've had from other sources - I was living in the U.K. when the first difference engine was completed, and it got a fair amount of attention in the popular science media - New Scientist and Physics World and the like.

-- Bill Sloman, Nijmegen

So, the perfect model for all computer hardware and software ever since!

For the software for Babbage's Analytical Engine, search on Ada Lovelace.

The Wikipedia article doesn't contradict anything I've got from other sources - she got quite a few column inches around 1990, when the London Science Museum got part of Babbage's Difference Engine working.

-- Bill Sloman, Nijmegen

-- Bill Sloman, Nijmegen

It's going back to Nathan Myhrvold in May 2009. Plenty of time to see it.

It's open to the public. Note the hours.

Admission is free but contributions are welcome.

More on the difference engine, with a video clip of it in operation:

I visited the London science museam a long time ago but I strongly recall a video showing they where using modern CNC machines to manufacture the components for the analytical engine.

Sorry. I didn't choose my words carefully enough. What the Wikipedia article actually says is that "The difference engine and printer were constructed to tolerances achievable with 19th century technology".

Regular numerically controlled machine tools don't do anything late nineteenth century lathes and milling machines couldn't do - it's just that the operators don't have to pay attention in the same way, and don't get as bored. There are some machines around that can work to closer tolerances than they could back in the 1890's but you didn't see them in the machine shops of the places where I worked.

-- Bill Sloman, Nijmegen

A Linux port is underway. ;-)

...

Isn't that kind of superfluous? I mean, arithmetic is what computers _DO_.

Watching the mechanical operation is fascinating - almost beautiful: This isn't the one I saw yesterday, but I can't find the link - this one has some talking heads, but it does have snippets of the machine in action:

Cheers! Rich

Rich Grise wrote: (snip)

Here is a more detailed demo:

It's the ultimate in real-life steampunk!

I also looked at the videos others posted (I read articles as this thing was being made, and wondered if I'd ever see it in operation - at least I've seen those videos). This is an odd incentive to visit the area - to see a piece of 150-year-old purely mechanical technology/ Unlike so much else from that area of the world, a difference engine probably won't come to me (if only this thing went on tour, like famous paintings do...). OTOH, 8,000 pieces of brass, iron and steel wouldn't cost THAT much, could it?

Exactly how much did it cost to make this (and the one in London)? I didn't see a price anywhere in any of these stories.

Will they actually use it to print and publish a book of mathematical tables? It appears that wasn't in the plans of making the machine, but I think they should - I'd buy a copy of such a book. This seems to be an obvious step, to finally use the machine as it was originally intended. That would truly, fully vindicate Mr. Babbage.

I found this story that says it cost one million dollars:

I heard that it wasn't necessarily tolerances, but money. The poor guy went broke before he ever got one built.

Thanks, Rich