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Hardware

Water Computing 309

Andrew_Cronin writes "This is a nice project that some one did at MIT on building some logic computation systems without using electrons.. So why not use water..."
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Water Computing

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  • by packeteer ( 566398 ) <packeteer@sub d i m e n s i o n . com> on Friday October 25, 2002 @10:45PM (#4535095)
    Doesn't anyone know? Water and computers dont mix. Make up yuour mind. You can either make fun of water-cooling OR make computers out of water.
    • clean off your motherboard real good with rubbing alchol. (turn computer off, discharge all capacitators and DOUSE it with rubbing alchol) then what you do is get distilled water... and ofcourse you then poar that all over your computer whilest its running. i did this for a speach class. everyone was in shock... after the speach teacher yelled at me i was then given the only a.


      so what were you saying?

    • Water and computers dont mix

      You're right. Only Aqua and Macs mix.

      Oh wait....
    • Keynes (Score:3, Interesting)

      by Zeinfeld ( 263942 )
      The idea predates the electrical computer. In the 1930s John Maynard Keynes had a water computer that was used to construct a model of the British economy. The computer stretched over a large country mansion.

      Konrad Zues' Z1 and Z2 machines were built somewhat later but used many of the same ideas, only in a much more compact space.

      Of course now we will have a bunch of idiot libertarians blasting Keynes. However Keynes and his computer are the reason why Britain pulled out of the depression before the war while in the US depression turned to slump. The problem came when Keynsianism became an idelology after his death, the solution to every problem was deficit spending, just like today some idiots think that the solution to every problem (including a deficit) is tax cuts.

    • Water AND computers don't mix? I guess then its "You can either make fun of water-cooling XOR make computers out of water"

  • by EvilCabbage ( 589836 ) on Friday October 25, 2002 @10:46PM (#4535099) Homepage
    .. how long until we see a computer constructed using bong water?
  • by account_deleted ( 4530225 ) on Friday October 25, 2002 @10:46PM (#4535103)
    Comment removed based on user account deletion
  • by srhuston ( 161786 ) on Friday October 25, 2002 @10:48PM (#4535106) Homepage Journal
    Brings new meaning to the term "Bit bucket"
  • I think it is a cool concept. EMP wouldn't be such a problem. Lugging the thing to a LAN party would. Imagine having to carry Hinkley and Schmidt as well as the device.
    • by Verteiron ( 224042 ) on Saturday October 26, 2002 @12:17AM (#4535442) Homepage
      Actually, it might not be that bad. Just drain it and put it in a box. Looks like most of the components are plastic, so it'll be pretty light. When you get to where you're going, just fill it from the tap.

      Instant computer... just add water!
  • So... (Score:5, Funny)

    by ackthpt ( 218170 ) on Friday October 25, 2002 @10:48PM (#4535108) Homepage Journal
    If you overclock it, can it cool itself?
  • by jpt.d ( 444929 ) <abfall&rogers,com> on Friday October 25, 2002 @10:48PM (#4535109)
    Will we use electricity to cool it? Well water is a very effective cooler on electronics, so why not do it the reverse when your water is your 'electronics'?

    ZZZZZZZZZZZZZZzzzzzzzzzzzzzzzAAAAAAAAAAAAAAAPppp pp pppppppppp

    YOUCH!!!!!

    DAMN ME!!!!! THAT !*!@# HURTS.

    Scratch that idea.
  • by wilburdg ( 178573 ) on Friday October 25, 2002 @10:49PM (#4535112)
    He says without electronics, not without electrons... Last time I checked a molecule of water had, oh say about 10 electrons in it...
    • Damn, I hate replying to my own post... Ok, ok, so he did say without electrons... But he meant without electronics... =)
    • Try 10 (2 per hydrogen, 6 on the oxygen)
      • Well, it's 10 but it's 1 on each hydrogen atom, 8 on the oxygen.
        • Except, of course, that assertion involves simplifying assumptions, too.

          We could go as far as high school chemistry and decide that there are 2 core 1s electrons definitely associated with the oxygen, plus four more electrons that are part of lone pairs on the oxygen (probably also mostly belonging to the oxygen atom). Then there's four electrons involved in the two sigma bonds joining the oxygen to the hydrogen. Simplest story is that it shares two with each hydrogen.

          If we break out the molecular orbital theory, then it starts to get kind of messy. At the lowest level, we have a really ugly n-body problem. We can't solve the Schrodinger equation analytically for this case, so we're limited to approximate numeric solutions. (Technically, we should really account for relativistic effects and use the Dirac equation, but that's overkill for lightweight atoms like these.)

          Even then, solving for the wavefunctions by whatever method only gives us a probability that electrons will be located nearest a given atom. In principle, occasionally all 10 electrons could actually be closest to one of the protons, but you would have to wait a loooooong time for it to happen.

          Oh, yes--if I wanted to be picky, I could also mention that pure water will still undergo spontanous autoionization to form H+ (H3O+, actually) and OH- ions, containing the same number of electrons, but now the wrong number of protons...

          One more, then I'm done. Liquid water actually tends to get kind of clumpy. In the so-called 'flickering cluster' model, water molecules in the liquid phase form short-lived hydrogen bonded clumps containing several (or even several tens of) water molecules. These clumps have an electron count that depends (of course) on their size.

          Water is actually an incredibly interesting beast, chemically speaking. We take it for granted because it is ubiquitous, but there is a tremendous amount of very interesting stuff that it can do.

  • by Lobsang ( 255003 ) on Friday October 25, 2002 @10:49PM (#4535114) Homepage
    Either that or the Slashdot crew already crashed the "Water Computer". :))
  • So why not use water..."

    Well, since the site is already slashdotted (only the title is showing up for me) i'll have to use all the power of my brain to guesstimate.

    Why not use water? The answer is simple really. If you can use such liquids to proform logical computations then it would be adventageous to use a liquid with a VERY high boiling point to prevent all your data from boiling off into steam...

    Hmmm... I can see it now "that data has to be uncompressed into steam, heat it up a bit."
  • burst into flames after the slashdotting.
  • 10 electrons in H20 (Score:2, Informative)

    by zedge ( 133214 )
    So it is not exactly true that they
    are computing without electrons.
  • by EvilAlien ( 133134 ) on Friday October 25, 2002 @10:51PM (#4535128) Journal
    ... its half full of beowulf clusters of water computing power.

    I couldn't resist, sorry.

    As we get closer and closer to microscoptic or at least very small computers, how long until the inevitable complex systems of neural nets combined with tiny computing devices self-organizes into something with capabilities outstripping an expert system... and into something like SkyNet in the Terminator movies?

    The self-organization of a complex system into a self-aware artificial intelligence is a chaos theory wet dream.

  • uh . . . this might be my fault. i told a bunch of people i tutored that electrons moved down a wire just like water moved down a pipe. it seemed to be the most effective analogy. but now someone has taken it too far!
  • Very cool, but I gotta ask two questions... 1) how to implement other operation: OR, NOT, etc. and 2) It looks like he lets the excess water simply run off... no method for collection or recycling.

    Naturally, this brings to mind all sorts of jokes about computers that can finally REALLY do windows. Still, one wonders: What's so original about this? Who hasn't operated a steam-driven computer while playing Myst or Riven?
    • by Anonymous Coward on Friday October 25, 2002 @11:12PM (#4535211)
      how to implement other operation: OR, NOT

      Simple. The author gives XOR and AND gates, formed from joining two streams together, without and without a control. (See the article for details, I haven't taken the time to look into it very deeply).

      Anyways, XOR's function number is 0110. Split it in two, and you get "A(01) when B=0, NOT A(10) when B=1"--two unary gates formed a binary gate. Split AND's function, 0001, and you get "0 when B=0, A when B=1". Trust me, this is easier than it seems. The unary gates are: 00=0, 01=B, 10=NOT B, and 11=1. Now that we got that out of the way:

      • 0 XOR A = A
      • 1 XOR A = NOT A
      • 0 AND A = 0
      • 1 AND A = A

      None of those are useful except 1^A=!A. We need NOT to complete our library of functions too. Now we can combine it with other gates like so using Boolean Algebra:

      NOT(A XOR B) = A XNOR B
      NOT(A AND B) = NOT(A) OR NOT(B)DeMorgan's Law
      NOT(A AND NOT(B)) = NOT(A) OR NOT(NOT(B)) = NOT(A) OR B
      And now, ladies and gentlement, I present to you, The OR Gate:

      not(not(a) and not(b)) = not(not(a)) or not(not(b)) = a or b

      This is constructed from: 1 xor ((1 xor a) and (1 xor b)), and of course the 1 is simply a constant flowing stream of high-power water. And obviously, since NAND is a universal gate, this can be done like so:

      1 xor (a and b) = a nand b
      NAND can make any gate, including NOT, which is then combined as we saw above to form OR, NOR, XOR, XNOR, and even inhibitation and implication if you please.

      Did that answer your question?

      -jc

    • by Xzzy ( 111297 )
      > 1) how to implement other operation: OR, NOT,

      well, following on the system he started you can probably get the effect of OR or NOT by altering how the "computer" reacts to the outputs, using the existing gate.

      You could make an OR gate by wiring the two outputs together. Get water in either jet, and you get a 1. Put water in both jets and you get a 1. Put no water in either jet, you get a 0.

      A NOT is just as simple, except you need a constant jet feeding through the gate. No water in the other jet means a 0 converts to a 1, water in both jets dumps into waste and creates a 0.

      So there you have it.. by tweaking he inputs/outputs of the single existing gate you can create pretty much any conditional you desire.
    • another problem (Score:3, Informative)

      by merriam ( 16227 )

      a not gate: an xor gate with true -- ie a constant stream -- applied to one input

      an or gate: an and gate with not gates at each input and output -- or just join two streams with a simple junction

      A recycling system is easily added. A more fundamental problem is that the gates are passive: there is no amplification. You can use gravity, but with feedback some lines will have to go upwards and need a complex pump for each line. Also you may need a lot of height per stage.

      Fluid actuated valves would solve this problem, and would be more efficient. Only one pump would be needed -- as in electronics -- to provide the supply pressure. But in the simple case of a four-bit adder, it might be harder to make.

  • Now that i see the project itself, a thought came to me...

    What if lego pulls a patent suit in order to only let children use them? Just think of all the tinkerers who will have to pay royalties in order to mount prototypes on legos... It's also quite funny to see a lego device hooked up with some tubes to this huge complex computer.
  • by dillon_rinker ( 17944 ) on Friday October 25, 2002 @10:55PM (#4535149) Homepage
    Scientific American had an article about water-based logic gates and circuits some decades ago. IIRC, they even created circuits that had no electronic analogy. I can find no reference to this on the web - perhaps some other science geek with access to a complete collection could find it. I believe it was in the Amateur Scientist, but it's been about fifteen years since I read through the stacks of magazines in the cabinets of my chemistry classroom, so I could be mistaken.

    For a similar concept (ie, non-silicon machine logic) that I first read about in the pages of Scientific American, check out the Apraphulians here [rustrans.co.uk]. For more info on this ancient race, Google is your friend. [rustrans.co.uk]
    • by friscolr ( 124774 ) on Friday October 25, 2002 @11:10PM (#4535202) Homepage
      In "The Way Things Work" (1988) David Macaulay also illustrates logic gates as plumbing in a building. It's on page 333 of the original book; the newer version even has an interesting rant about Bill Gates.

      i always liked old school water clocks.

      i seem to recall something about logic gates or some sort of logic being built out of matchboxes and beans. it played tictactoe, deciding the best move by plopping out a bean of a certain colour? i can remember neither the details nor the source.

      • i seem to recall something about logic gates or some sort of logic being built out of matchboxes and beans. it played tictactoe, deciding the best move by plopping out a bean of a certain colour? i can remember neither the details nor the source.


        I've seen it in a book by Martin Gardner, the game was called Hexapawn. A quick search on google should turn up more details.
        • i seem to recall something about logic gates or some sort of logic being built out of matchboxes and beans. it played tictactoe, deciding the best move by plopping out a bean of a certain colour? i can remember neither the details nor the source.
          I've seen it in a book by Martin Gardner, the game was called Hexapawn. A quick search on google should turn up more details.
          Interesting! In short: it's an exhaustive search of all moves from black's perspective whereby all moves are initially possible and a loss causes the last move to be removed as a choice. I found the info here [mactech.com]. There's more at the site including how to implement it programatically.

          Here's their explanation of the matchbox version of the game:

          Gardner's machine is implemented as a set of 24 matchboxes, one for each possible board position when it is Black's move. Each matchbox has pasted on it a drawing showing this board position, as well as all possible moves from that position, drawn in different colors. Inside each matchbox are several colored beads, one for each move on the top. When it is the machine's turn to move, the human operator finds the matchbox showing the current position, draws a bead at random from the matchbox, replaces it, and makes the move thus chosen. The machine learns from its losses: when it loses, the operator removes and discards the last bead drawn. This ensures that the machine will never lose in this way again.

          To keep this on topic: this game could be implemented with a water computer, too. Replace the matchboxes with different colored buckets of water. Instead of removing a bead for a loss, dump out the corresponding bucket.

          For a more enjoyable game, replace the buckets of water with shots of beer. =)

    • Speaking of logic, here's a October 1989 Scientific American article detailing the tinkertoy tic-tac-toe playing machine [rutgers.edu]. Anybody want to make this out of these water logic components? Didn't think so... ;)
      • As the article states this is currently on display in the main entrance to the Boston science museum. it looks really darn cool but it just sits there, no demonstrations or anything. I think they are afraid any actual usage will break the thing. :/

        Here's a better image of the contraption [sigmaxi.org]
    • I know a guy that builds machines with "air logic". I don't think it is that different of a concept, both are fluids, although one is liquid, the other gasseous.

      I think this air logic allowed him to run a machine in hazardous material atmospheres, where any risk of electrical components causing a spark was unacceptable. It was mostly for manufacturing and control.
    • The "apraphulian computer" article in 1988 was an April Fool's joke. A.K. Dewdney has a history of presenting interesting scientific concepts as fiction. You can find examples of this style of presentation in his book Planiverse [amazon.com] as well as some of the earlier corewars articles in Scientific American IIRC.
  • I wonder if using water as a medium can allow it to do someoperations very efficiently, (at least in comparitive scale) operations like addition and subtraction might be accomplished through butting all of the water from cell one to cell two, or the greater then operations could involve wichever is heavier. I think it is an interesting way to look at the rudementury operations.
  • Very good (Score:5, Interesting)

    by Istealmymusic ( 573079 ) on Friday October 25, 2002 @10:58PM (#4535163) Homepage Journal
    I remember of Neal Stephenson's Cryptonomicon, where when L.P.Waterhouse was walking amongst the beach at sundown, in a starlit avenue, and he drew lines in the sand. This was inspiration for barcodes, but that's beside the point. The point is Stephenson had the narrator narrate L.P.Waterhouse notice how the ocean is a Turing machine, it interacts with the sand, due to certain mathematical fluidity properties, to leave an indentation of predictable properties.

    I've considered water-based computation long ago, but hats off to this student for logic design and implementation. My idea was to have water push open another wate gate, much like a flow-controlled valve, allowing for a water-based transistor. Combine this with other transistors, and you can build virtually any gate--I take that back, any gate you want. XOR and AND are good choices, as with a XOR a you can get NOT, to make a NAND, and as we all know NAND is the Univesal Binary Gate.

    • Re:Very good (Score:3, Interesting)

      by Idarubicin ( 579475 )
      NAND is the Univesal Binary Gate.

      In principle, couldn't XOR be used to construct all the other gates as well? Who needs a NAND explicitly? You can make an AND from XORs. An as stated, you can also get a NOT from XORs.

      Yes, of course you can build up all the NANDs you need from XORs, and then use those composite gates to build the rest of the gates--but it's more efficient to skip the middle step of constructing the NANDs.

      • If you show me how to make ANDs from XORs, I'd be impressed. Here are my findings, breakthroughs highlighted in bold:
        • 0 xor A=A
        • 1 xor A=not A
        • A xor A=1
        • not (A xor B) = A xnor B
        • 0 xnor A=not A
        • 1 xnor A=A
        • A xnor A=0

        That's all you can create from XOR. The unary NOT, unary buffer, and the useless unary constant functions--to my knowledge.

        I vaguely remember "proving" only NOR and NAND are universal gates in my childhood, but that has long since passed. What am I missing, perhaps an equation involving an XOR with NOT on one side, or usage of the oddball binary inhibitation and implication gates?

        • Okay, there may be a more efficient way to do this, but I just sketched something out.

          not(A xor {not[((not A) xor B) xor ((not B) xor A)]})

          I think is equivalent to A and B. (not A is just A xor 1, so I didn't write that explicitly.) There's probably a more efficient solution, and I have to go out this morning so I'm not absolutely certain of my notation above...translating whiteboard to Slashcomment is not my forte.

          • Dammit. I knew I shouldn't have rushed.

            I'm wrong; don't bother trying to check my work. Sigh. Making an AND out of XOR probably *is* impossible.

    • good indeed. Sounds like basic hydraulic control circuits, easily implemented with hydraulic moving cylinder switches or AOV like diaphrams. Diapharm takes signal from flow to acuate further flow.

      First drill a small hole through your bar stock for flow. This is a restriction of flow so that your controler can work. Now drill a larger hole through the length of your bar stock that intersects and devides the smaller hole and hone it well. Now shove a machined cylinder with a hole into the larger hole. When you move the cylinder with the hole in it to line up with your flow path, you have an open switch. When the flow path is obstructed with the larger cylinder, you have a closed switch. The degree of obstruction determines the amount that flows. You, of course, will have to use O-rings on the cylinder and weep holes in the barstock the feed to a return to make this switch pratical. A spring is used to keep our cyliner in place and two diaphams or small hydraulic rams can be set up on either side to make an exclusive nor gate. A not gate would have only a spring and one diaphram. As you say, you can build any gate like this.

  • Who else tried this? (Score:5, Interesting)

    by thekernel32 ( 240428 ) on Friday October 25, 2002 @10:59PM (#4535167) Homepage
    I really remember seeing a documentary on how the russians tried using water logic for computations and got pretty good with it back in the 40's. Then again they did alot of cool stuff over in that part of the world. They actually managed to stick with 50's technology for 40 years. yay communism! I knew someone who had no more after the berlin wall came down just because his job was dependent upon the crappy stuff they made breaking down. Reliable products from the west caused alot of people to loose their jobs.

    I know it's an off topic rant, wanna give me some points for being interesting anyway?
  • Maybe you cool a water computer with silicon? ;-) Sorry.
  • by Cheetah86 ( 136854 ) on Friday October 25, 2002 @11:01PM (#4535175) Homepage
    <sarcasm>Looks like we "flooded" the server...</sarcasm>
  • by 7-Vodka ( 195504 ) on Friday October 25, 2002 @11:03PM (#4535182) Journal
    But the thought just came to me of using beer instead of water. That way you could make a beer computer! Who says beer makes you shite at math? you CAN get drunk and still do 4 bit additions :)

    Hell, take that thing on a pub crawl and have your beer do it's own calculations of how much tip you should leave as it's on it's way down to your stomach!

  • So, a beowulf cluster could flood a city block if it was OCed and burned out....

    Now the guy can do basic logic, but this must be very slow. It is wonderfull seeing someone trying to educate people about computers. Most people have no idea what an XOR gate is, or a transistor for that matter. Well I wish him good luck.

    Please ignore above troll
  • so many youngsters (Score:2, Interesting)

    by Anonymous Coward
    Why logic gates? you can go straight to integration and computing outcomes of complex systems using water in analog circuit - some uk bunch did it back in the 50's or so for modelling the economy - and was used for such - and was still better at numerical answers for the problem until well into the 70's.
  • by matman ( 71405 ) on Friday October 25, 2002 @11:37PM (#4535295)
    I wonder if it would be possible to create such gates that function on water pressure changes. It's quite quick to propigate a wave through water. I'm talking about pressurizing water inside of the system, and then inducing shock waves from your inputs. Could you make gates that trigger on those pressure changes? You could probably get quite a few bps (by creating shock waves in the water) I wonder if you could just use plain old speakers to generate sound waves... I wonder what the attenuation characteristics of water are.
  • Why not extend the metaphor...

    Inductance is the same as momentum. You could build a gadget that has a turbine in the water flow with a fly wheel attached. The gadget would resist water flow starting up, and would resist the water flow slowing down once it's moving. (same as an inductor fighting a change in current)

    Capacitance is the same as a flexible membrane across the pipe, which will transmit AC changes in pressure, but not DC.

    You could build a capacitor/inductor tuned circuit that either filters or passes certain frequency water waves

    Also, water transistors should be fun. A small flow or pressure of water controls a larger flow or pressure (in either an analog or digital fashion)

    It would be a way fun tool for teaching electronics.

    • Actually in Russia (Score:5, Informative)

      by WetCat ( 558132 ) on Saturday October 26, 2002 @12:47AM (#4535523)
      ... water analog computers have been used since 1949... till mid 80-x for modelling differential equations.
      They were used for large-scale projects, such as modelling of water dams.
      • In the London science museum they have an analog water computer that represents the British economy. I believe it predates 1949. I am not sure how accurate a model it was, but it cant be much worse that the digital model they have now.

        Reseach shows the more higly qualified an economist is, the poorer his predictions!

  • by Alsee ( 515537 ) on Friday October 25, 2002 @11:51PM (#4535349) Homepage
    Every time I try to overclock it, all the circuits freeze up.

    We're thinking of giving up on liquid nitrogen and trying liquid helium.

    -
  • Note the logic gates. [ebay.com]

    Many equations were solved with that fine machine.

  • by Alien Being ( 18488 ) on Saturday October 26, 2002 @12:05AM (#4535401)
    better pipelining.
  • Slashdotting and UFie-ing (This was selected as the UF link of the day today), both at once.. shame, shame...

    --j0shua
  • Re: (Score:2, Funny)

    Comment removed based on user account deletion
  • by jacobjyu ( 583486 )
    Imagine overclocking this baby.. just hook it up to Hoover Dam and you'd be able to run Quake3 easy.. but then again, you better have a monitor with a water input.. and a keyboard and mouse with water out
  • by gargle ( 97883 )
    But there's no gain.
  • a water adder (Score:5, Insightful)

    by drDugan ( 219551 ) on Saturday October 26, 2002 @12:37AM (#4535498) Homepage
    a friend of mine in college (Aron) made a water adder capable of adding two 8-bit values -- all with water streams.

    LINK [bowdoin.edu]

  • by Chagrin ( 128939 ) on Saturday October 26, 2002 @12:51AM (#4535532) Homepage
    Didn't we just have a different "font" article?
  • by Mark Garrett ( 607692 ) on Saturday October 26, 2002 @02:29AM (#4535756)
    ... but I bet that in a few months, it'll all just turn out to be vaporware.
  • I remember reading an article (possibly in Scientific American or Science News) about making a DNA computer and using it to quickly solve the trip planning problem. It seemed a very cool hack but a long way from being practical.

    On the other hand the speed of molecular reactions and their ability for massive parallelity (is that a word?) sounds like it would hold promise for certain types of computers.

    This of course would leave Steve Jobs to insist that his MISC computers were much better even if they were a terahertz or so behind current Pentiums.
  • by Animats ( 122034 ) on Saturday October 26, 2002 @02:39AM (#4535773) Homepage
    Fluidic logic [si.edu] has been around since the 1960s. It's often used in industrial process control. It works for both air and liquids. Most industrial systems use air logic, but automatic transmissions often have fluidic logic running on hydraulic fluid.

    The MIT students didn't quite get it right. Their gadget doesn't seem to have gain. The key insight needed for fluidics is that a jet of fluid can be diverted with a smaller jet coming in from the side. This allows building a fluidic amplifier.

    Once you have an amplifier, you can do switches, gates, flip-flops, and other logic elements. Analog control systems, with fluidic sensors and amplifiers driving pneumatic or hydraulic cylinders, are also possible. When the inputs and outputs are pneumatic or hydraulic, it's often convenient if the control system is, too. Fluidic elements are very reliable, too - there are no moving parts except the working fluid.

    One wierd fluidic application is this kosher public address system. [216.239.53.100]

  • The Bay Model (Score:2, Informative)

    by bgspence ( 155914 )
    The Bay Model in Sausalio is a huge water based analog computer. Check it out at the army page [army.mil] or this VR view [virtualguidebooks.com].
  • ...to the term core dump!
    I wonder if this machine also has an overflow bit!?
  • by haggar ( 72771 ) on Saturday October 26, 2002 @04:04AM (#4535908) Homepage Journal
    (I say "calculators" because I think that computer is underrated).

    I have studied about these machines at Uni (I studied in eastern Europe): they use fluids and analog pseudo-circuits to create things like integrators, adders etc. and are capable of solving systems of differential equations in real time. This kind of equations is still a non-trivial problem for digital computers.

    However, with the advent of gigabit-clocked CPUs, these machines are definitely out. Their models are, sometimes, replicated in software, though.

  • I believe it was in the book Lord of the Files (William Golding would spin in his grave if he knew how many schoolkids misspell HIS book) that I read about a mad scientist building the game of Defender using cows milling through an intricate system of pens and gates spread out over several acres of farmland. The gates were wired and the inventor had an array of light bulbs as the display. You have a friend in the business, indeed. :-)

    Ohh, I just found another quote from the book that I once used in a software manual:

    Prestel screen-dump, ASCII string,

    Punched tape reader, Token Ring,
    Matrix output, raster scan,
    Printer sharing via LAN,
    Transputer network, thirty mips,
    Configured in the moonís eclipse.
    ROM-based firmware, network nodes,
    User-friendly input modes,
    Duplex transfer, RISC machine,
    Jump to user subroutine,
    Write it to a backup file,
    Press return, compile, compile!
    - Ray Girvan and Steve Jones
  • Hasn't anybody heard about the Phillips Machine, used for computing national economies?

    The BBC has just done a radio program on Bill Phillips' invention. You can still hear it on

    http://www.bbc.co.uk/radio4/science/electronicbr ai ns.shtml

    --
    el bid

  • by rwa2 ( 4391 ) on Saturday October 26, 2002 @11:01AM (#4536647) Homepage Journal
    I saw a guy do a presentation on this during an ASME conference. The Russians have been using the same technology with air rather than water to construct logic gates and op amps for missile controllers and such. I suppose the benefits were not needing electricity - just run the thing off of compressed air, which is readily available in a missle.

    Actually, the main benefit was that it was no longer susceptible to electromagnetic interference, so you could build very noise-free amplifiers.

    The samples that the guy had were much smaller... about 2-3cm squre wafer-thin metal plates. Each plate had a pattern on them which were machined out to form components. Circuits were built by "sandwiching" a series of plates together, so the outputs from one component could feed into the input of the next component. The resulting devices would be several cm long consisting of dozens of components bolted together with long stringers.

    The theory looked about the same as the MIT guy's device, though. I think the Russians developed most of the counterparts to electronic components, though - various transducers and transistors. I'm not sure how they would have done something like a diode,though...

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