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Building a 5-Ton Calculator From 19th-Century Plans
alphadogg writes "Starting in May, many will have the opportunity to see computing done the old-fashioned way: with lots of gears, a big crank, and some muscle. The Computer History Museum in Mountain View, CA, will unveil a new construction, the first in the US, of the 19th-century British mathematician Charles Babbage's Difference Engine No. 2, an improved version of his earlier design for a mechanical digital calculator. It weighs in at two tons more than the Difference Engine built in 1991 at London's Science Museum. Microsoft millionaire Nathan Myhrvold commissioned and paid for the US model."
Does this mean as a sysadmin that I should start wearing my Frock and Tophat and subscribe to the local Victorian club???? :)
How amazed would you be to suddenly find that you just forgot what I wrote and you needed to reread my post.... again.
yes, and we can all imagine a beowolf cluster of them, comparisons with automobile tonnage, and how in soviet russia, 2 tonn calculator uses YOU.
yep.
Ice Cream has no bones.
What happens when you divide by zero on a calculator using a physical engine?
Does it explode? Will it create a black hole? Could this be the next doomsday device?
We do what we must
Because we can.
Yes, but first you have to figure out how to approximate Linux as a Taylor series.
WELCOME TO THE BABBAGE ANALYTICAL TIMESHARING SERVICE
PLEASE NOTE THAT THE INTEGRATOR IS CURRENTLY UNAVAILABLE
DUE TO THE WEEKLY GREASING SCHEDULE. WOULD ALL USERS KINDLY
RETURN ANY UNUSED PLUGBOARDS, AS THE PROGRAMMING TEAM ARE
RUNNING LOW. DIVISION UNIT 3 WILL BE OUT OF ACTION UNTIL
THURSDAY DUE TO EMERGENCY COG REPLACEMENT - PLEASE ENSURE
THAT YOUR PROGRAM DOES NOT ATTEMPT TO DIVIDE BY ZERO AS
THIS CAN CAUSE SEVERE DAMAGE (INCLUDING SHAFT BREAKAGES).
.
.
SYSTEM READY.
?
Hail Eris, full of mischief...
E pluribus sanguinem
I'm am one of the Docents for the Difference Engine #2, and although the team making it work is WAAAAY more competent to comment, lemme put out a few FACTS, at the risk of "flame wars of death"... The Engine is a single function calculator that can iterate the values of a 7th order polynomial approximation to an arbitrary mathematical function. After about an hour of VERY careful setup, any set of coefficients could be entered, allowing almost any function to realized. It uses a technique called "finite differences" that allows the calculation to be performed using only addition (and 10's compliment coefficients to represent negative numbers). Our working plan is to set it up to do a table of logarithms, much like Babbage's own table, produced well before he thought of Difference Engine #2. The polynomial approximation for logarithms is quite accurate over the space from 1.0 to 1.6, 6000 iterations of the Engine. (It takes four turns of the crank or about 6 sec. per iteration.)
The calculation section has about 4,000 parts, and a very elaborate printer mechanism has another 4,000, and was designed to produce sterotype molds of a complete page of a book of tables.
It is a WONDEROUS device to behold! There are 52 distinct stages in it's control graph (EXACTLY like a modern timing diagram, just vertical...) An elaborate nest of 14 cams control the complex sequence of events to do an iteration, which is !pipelined!. The sinuous ripple carry mechanisms on the back side are HYPNOTIC, as are the forward and backward movements of the intra-column sector gears.
Avoid CHM on May 10, it's gonna be a madhouse! But this is pretty close to the top of the list of "1000 Geeky Things to See Before You Die", oh, and by the way, there's all the other ABSOLUTELY WAY COOL stuff at CHM, wanna see an Apple I signed by "the Woz"...
YOU GOTTA SEE THIS! chmguy
Actually, it is at least possible that it was intended as a trick question. You know, one where if you say "yes" then you've just said "yep, I'm a con artist." Admittedly, it's a stupid one even as trick questions go, but still, there might be some purpose behind it.
To put things into perspective Babbage got funding for one machine, never finished it, decided he's rather begin designing the version 2 model, asked for more funding, repeat ad nauseam. Pretty much it was _the_ original computing vapourware. Pretty soon he got no more funding, but that never stopped him from asking for more and hyping his unproven creation to the parliament.
He also seems to have descended into a nerd-like bitterness, in which he took such questions out of context as proof that everyone else is a drooling idiot and that's why they don't see he's right. And in that he also included such questions as, basically, "well, what _can_ it do?" and "what's the business advantage for making one of these?" Stuff that you'd get asked by any business nowadays too. He took them as proof that his contemporary Englishmen were narrow minded and lacking in vision.
It may seem obvious in retrospect that his design was right, but at the time it was everything except obvious. It was a _monumental_ expense with the economy and technology at that time, even compared to paying armies of people to calculate those by hand. And it was anything but proven. Noone knew if it would even work at all. Again, the first round of funding he got, produced nothing tangible.
Also regarding the parliament at the time, they were not as obtuse as you (or Babbage) seem to think. They funded a lot of research, actually. The nautical clock, for example, was paid for by the parliament, and that was quite the iterative development. The first couple of versions not only were too inexact to be any use, but at least the first one didn't even compensate for the ship's rolling around. But nevertheless, that guy had _something_ working to show for his work, and kept getting more money to keep working. Babbage had nothing except his claims.
Now before I sound too damning to Babbage, it wasn't only his fault. He got into a conflict with the company actually building it, and that was the chief reason why the V1 was never completed. But, still, seen from outside, he never had anything working to show, and even more damning he just unilaterally scrapped the design in the middle of the project and began designing an even more overengineered V2 instead.
So, anyway, given that he was technically hyping vapourware, I can see a smart-arse member of the parliament trying to catch him with a trick question. Again, it _is_ a dumb one, but it's not the same class of dumb as actually thinking that a machine can magically guess the right answers when fed wrong data.
(But then again, I see a ton of PHBs and businesses nowadays believing just that about electronic computers, so maybe it was just a dumb question after all.)
A polar bear is a cartesian bear after a coordinate transform.