Slashdot is powered by your submissions, so send in your scoop

 



Forgot your password?
typodupeerror
×
Hardware Hacking The Military Build Science Technology

"Nuclear Archaeology" Inspires Replica of Hiroshima's Little Boy 298

James Cho writes "Through a decade of painstaking reverse engineering, trucker John Coster-Mullen built the first accurate replica of the Hiroshima bomb. His work yielded a new history of the first nukes, 'Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man,' with historian Robert Norris saying, 'Nothing else in the Manhattan Project literature comes close.' Philip Morrison, one of the physicists who helped invent the bomb, deemed it 'a remarkable job.'"
This discussion has been archived. No new comments can be posted.

"Nuclear Archaeology" Inspires Replica of Hiroshima's Little Boy

Comments Filter:
  • by 4D6963 ( 933028 ) on Sunday January 25, 2009 @02:23PM (#26600093)
    *BOOM*
    • by RichardJenkins ( 1362463 ) on Sunday January 25, 2009 @03:07PM (#26600507)

      Hopefully not that accurate.

    • by demachina ( 71715 ) on Sunday January 25, 2009 @10:45PM (#26603975)

      Its a little sad to skim through the posts on this story and find pretty much all of them are lame.

      Its a long article but its really a fascinating read and I'm guessing almost no one did. It makes a couple really insightful points:

      A. All of the U.S. governments obsessive secrecy about nuclear bomb technology is pure security theater. The hard part is mastering the fuel cycle. If you can acquire the fuel or master the fuel cycle, making the bomb is pretty easy.

      B. Much of what we read and take for authoritative is in fact garbage. There have apparently been a number of works on Fat Man and Little Boy, often by well educated and authoritative authors that were apparently complete nonsense. It just took an obsessive photographer/truck driver with no college degree to debunk one authoritative work after another. In particular apparently everyone thought the Uranium bomb was a female target shot with a male shaped projectile because thats the way people expected it to be, when in fact it appears it was the other way around.

      One also wonders if the U.S. government intentionally propagated nonsense in these "authoritative" works thinking it would set back some aspiring bomb maker. For example, in one work it apparently said the barrel in the Uranium bomb was made of wood which was apparently pretty comical since it had to contain the explosion of several bags of cordite.

      • by cyn1c77 ( 928549 ) on Monday January 26, 2009 @11:59AM (#26608799)

        Get it straight.

        The US government does not confirm or deny comments on classified technology. Nuclear weapons are classified. So if you write a book that is full of crap on nuclear bombs, all of the experts will general work for (or have worked for) the government and will not be able to comment on it.

        Thus, people who are not in "the know" will read the book and say "Gee, this is really great stuff, very accurate." Meanwhile those who actually work on these weapons and who have security clearances will buy the book, read the book, laugh about the errors with each other... and not talk about it to the general public.

        It's easy to be a self-proclaimed expert when all the real experts can't comment and you can't actually demonstrate that your technology works.

        And finally, you really think making a bomb is easy if you have the fuel? Do you have personal experience here? Keep in mind you don't get a lot of testing opportunities with these things, and diagnosing what is going on during the explosion is also quite involved. There's a big difference between assembling your nuclear material to generate some nuclear yield and actually generating significant nuclear yield.

  • How soon until... (Score:5, Insightful)

    by www.sorehands.com ( 142825 ) on Sunday January 25, 2009 @02:26PM (#26600125) Homepage

    How soon until homeland security shows up accusing him of terrorism?

    • by philspear ( 1142299 ) on Sunday January 25, 2009 @02:30PM (#26600159)

      If he's built a WORKING replica, I would hope VERY soon!

      • by sidb ( 530400 ) on Sunday January 25, 2009 @02:48PM (#26600319) Homepage
        A working replica would be dangerous and surely illegal. It would not be terrorism unless he used it deliberately to terrorize a group of people. Just because something is bad doesn't make it terrorism.
        • by PolygamousRanchKid ( 1290638 ) on Sunday January 25, 2009 @03:06PM (#26600499)

          A working replica would be dangerous and surely illegal.

          If I had a working replica of a nuclear bomb in my basement, I don't think I would give a rat's ass about whether it was dangerous or illegal.

          If I did have a nuclear bomb, I would not have a problem.

          Some other folks would have a problem.

          • Re: (Score:2, Offtopic)

            by _Sprocket_ ( 42527 )

            If you decided on being someone else's problem, you'd go to sleep one night and no longer be anybody's problem.

          • If I did have a nuclear bomb, I would not have a problem.
            Some other folks would have a problem.

            Said The Mouse that Roared [wikipedia.org] :-)

          • Re: (Score:2, Insightful)

            Right, because it's a well known scientific fact that those who actually make a bomb are totally immune to the bomb's effects.

            Besides, having explosives is not illegal just because you could use them for therrorism, but because accidents happen; accidents which might not only harm yourself (being stupid enough to have a bomb with you, whatever happens, you had it coming), but those around you as well. More so with something as powerful as a nuke.
          • Radiation Poisoning? Cancer?
          • by PopeRatzo ( 965947 ) * on Sunday January 25, 2009 @05:35PM (#26601783) Journal

            If I did have a nuclear bomb, I would not have a problem.

            Some other folks would have a problem.

            This was precisely America's attitude about nuclear weapons for more than thirty years after Trinity.

            Turns out they were wrong. There was no way to say England yes, France no, India yes, Pakistan no, Israel yes, Iran no.

            The Atomic Bomb created the sense in American leaders that our overwhelming advantage in power created an American hegemony.

            Like the Jurassic Park geneticist believing his "sterile" dinos would not spread, Truman and subsequent presidents believed in the myth of "control" that would keep the genie in the bottle. Worse, they thought they could be the "decider" of who gets to rub the lamp and who doesn't.

            Me, I just hope Fallout 3 doesn't turn out to be predictive. I've run out of Rad-Away.

          • by Luscious868 ( 679143 ) on Sunday January 25, 2009 @05:49PM (#26601873)

            If I did have a nuclear bomb, I would not have a problem. Some other folks would have a problem.

            Signed,

            Ayatollah Ali Khamenei

          • If I did have a nuclear bomb, I would not have a problem.

            I think you're vastly underestimating a nuclear weapon's potential to ruin your day.

          • Re: (Score:3, Informative)

            by JWSmythe ( 446288 ) *

            Nope, if you had a working replica bomb in your basement, you'd never know when it went off. You'd simply be vaporized, as would your neighbors for a few miles. When they identified the center of the crater, then they'd know it was you, but there wouldn't be much to prosecute. I don't think they'd try to prosecute "the atoms previously known as Polygamous Ranch Kid".

            Skewing slightly off topic, how the heck do you manage to be polygamous? I can only handle being with one wom

        • by Anonymous Coward on Sunday January 25, 2009 @03:24PM (#26600639)

          I think the law at least in CA says there's $200 fine for detonating one...

          • A quick check of the California Code [ca.gov] for the word 'nuclear' finds that no law along those lines exists on the books, though that doesn't mean that something like it didn't exist before. I suspect the fine would have been far higher, though.

          • Its a municipal code in some town in CA, not a state law.
          • Re: (Score:2, Interesting)

            Well, it's a little steeper than a fine, but I still think it's pretty funny that there's a state law for this:

            11418. (a) (1) Any person, without lawful authority, who possesses, develops, manufactures, produces, transfers, acquires, or retains any weapon of mass destruction, shall be punished by imprisonment in the state prison for 4, 8, or 12 years.

            (California Penal Code)
          • Re: (Score:3, Funny)

            by Pollardito ( 781263 )
            I believe it's ok in California as long as the bomb mechanism is a female target shot with a male projectile, rather than a male target by a male projectile
        • Just because something is bad doesn't make it terrorism.

          Yes of course, but I don't care what it's called, I do not want individuals (or even governments, including my own) to have nuclear weapons. If the thing worked, you could call it "super happy nuclear archeology," and I wouldn't mind just as long as SOMEONE took it away from the guy.

        • by nurb432 ( 527695 )

          No, it wouldn't be dangerous.

          Illegal, sure due to the idiots making the rules, but an inanimate object cant be dangerous on its own.

          • Re: (Score:3, Funny)

            by Hognoxious ( 631665 )

            an inanimate object cant be dangerous on its own.

            If you're going to quote the mayor of Pompei, at least give proper attribution.

        • If the government wants it to be terrorism in order to invoke the removal of your civil rights, then it is terrorism.
      • by telchine ( 719345 ) on Sunday January 25, 2009 @02:50PM (#26600331)

        If he's built a WORKING replica, I would hope VERY soon!

        Nuclear bombs don't kill people. People kill people. Why shouldn't this guy have a born right to bear nuclear arms? If he wants to defend his property from double-glazing salesman, he should have every right to make use of the second amendment and protect his property!

      • Comment removed based on user account deletion
      • by hitmark ( 640295 )

        i guess it depends on what one define as working.

        it could be that all the parts (detonators and such) work, but is missing that vital nuclear core.

        iirc, fat man was the "cannon" driven uranium bomb...

        • Re: (Score:2, Informative)

          by Anonymous Coward

          iirc, fat man was the "cannon" driven uranium bomb...

          Fat Man was the implosion type. Little Boy was the gun type.

        • Re: (Score:3, Informative)

          by NouberNou ( 1105915 )
          Fat Man was the implosion device. It was called Fat Man due to the size of the explosive lenses that were used to compress the Plutonium into a critical mass. Little Boy was the gun-type device.
      • by mpe ( 36238 )
        If he's built a WORKING replica, I would hope VERY soon!

        If it's a working replica they might want to stay at least two and a half miles from it.
      • by T5 ( 308759 )

        The trick to nuclear weapons is, and will always be, manufacturing of the fuel. Uranium enrichment and plutonium manufacture require enormous budgets, know-how, and persistence. Neutron enhancers like lithium deuteride and tritium in quantity aren't available from Walmart. A country with defensible borders where you can build/hide/lie to the IAEA about your manufacturing and engineering facilities is a plus.

        With no disrespect toward the weapons engineers, the rest of the process is exactly that - a proce

    • Re:How soon until... (Score:5, Interesting)

      by Daniel Dvorkin ( 106857 ) * on Sunday January 25, 2009 @02:35PM (#26600211) Homepage Journal

      According to Amazon, his book was published in 2002. If they were going to lock him up, they've had plenty of time to do so already.

      Of course, it's a good thing for him his name is John Coster-Mullen instead of, oh, say, Ahmed al-Rashad. You can pretty much guarantee that in the latter case, even if all the other circumstances were exactly the same, he'd have been disappeared a long time ago.

    • by nurb432 ( 527695 )

      I bet they already did.

  • by 4D6963 ( 933028 )
    Is my mind just twisted or is there an innuendo of sorts in the fact that the article is titled Atomic John, with a photograph below of the guy in question and a huge atomic phallic substitute seeming to come out of his crotch?
    • No, if that were the case, he would have built "Fat Man," the Nagasaki one.

  • by 93 Escort Wagon ( 326346 ) on Sunday January 25, 2009 @02:40PM (#26600251)

    FR1ST PEDANTIC POST

    The guy went through declassified government documents to gather all the information he could find (including design information), and went from there. I don't think this is anything like reverse engineering.

    If he "reverse engineered" the bomb, wouldn't it mean he put the design together based on blast data from known explosions of this particular device?

    • by Daniel Dvorkin ( 106857 ) * on Sunday January 25, 2009 @02:51PM (#26600349) Homepage Journal

      "Reverse engineering" is a pretty broad phrase. It can mean anything from taking an actual working example of a machine and figuring out how to build it, to the kind of thing you're talking about, observing what a machine does and figuring out how to build something that does the same thing (whether or not the internal mechanism is the same.) I'd say what Coster-Mullen did falls right in the middle of this range, so calling it "reverse engineering" is fair.

    • by Wiseleo ( 15092 )

      Given fragment 0.5"x1"x2" figure out the curvature of a portion of a payload of unknown shape and size.

      If that's not reverse engineering - recreating the initial object from a tiny fragment, I don't know what is. :)

      Given a large quantity of misleading, inaccurate, and downright incorrect data figure out the reasons for anomalies. Sounds like reverse engineering to me.

      I've read the entire article, have you?

  • by B5_geek ( 638928 ) on Sunday January 25, 2009 @02:44PM (#26600281)

    While many people may exclaim that this information is 'dangerous' to be released in the public domain let me remind you of a few small details.

    1) ANY high-school/college student should be able to tell you what the critical mass of U235/238 is.
    2) Most handymen should be able to make atleast ONE method of creating a critical mass pile.
    3) It takes a GOVERNMENT to build multiple copies and revisions and tests to make it bigger/better.

    This information does not mean "the terrorists can now make a bomb!" This changes NOTHING that hasn't been known for 50+ years. I would rather live in a society that does not suffer a knee-jerk reaction everytime something unusual is expressed. If anybody knows if this place exists, let me know; I'll start packing.

    • Re: (Score:3, Insightful)

      by Tacvek ( 948259 )

      The simple facts are that he (a truck driver!) is collecting detailed information about some of the worlds least efficient nuclear bomb designs. Bombs with the same amount of equal quality fissile material can be made far more powerful. No terrorist orginaization would want to create such wasteful bombs, so the information he is publishing is not very dangerous at all. Besides, a lot of the difficulty in making even an inefficient nuclear bomb at all obtaining the weapons grade fissile material.

      Now his mate

      • Re: (Score:2, Insightful)

        by NouberNou ( 1105915 )

        No terrorist orginaization would want to create such wasteful bombs, so the information he is publishing is not very dangerous at all.

        You seriously think that a terrorist organization would NOT take any sort of nuclear weapon?

        Little Boy and Fat Man were in the 13-20 kiloton range. More than enough to kill a few hundred thousand people in a dense urban target like New York or LA or any other major American city!

        • Re: (Score:3, Interesting)

          by vlm ( 69642 )

          No terrorist orginaization would want to create such wasteful bombs, so the information he is publishing is not very dangerous at all.

          You seriously think that a terrorist organization would NOT take any sort of nuclear weapon?

          You don't understand terrorism. All you need to create terror and cause chaos and evacuations is a bomb that is just dirty enough to make a geiger counter click somewhat above background rate in front of a TV camera. Heck a granite countertop would probably do (they are quite radioactive). Although potassium based salt substitute (also quite radioactive) is scarier looking. One "real bomb" might destroy a city. But ten thousand hand grenades detonated in the ten thousand largest cities all going clicky

        • by mpe ( 36238 )
          You seriously think that a terrorist organization would NOT take any sort of nuclear weapon?

          The goal of terrorists is to create terror. Some terrorists will do this using fake bombs or simply the threat of bombs. There are also terrorists who don't use any kind of bombs. Even terrorists who do use actual bombs may be more interested in getting fairly small bombs very close to specific people (or groups of people).
          Someone like Ted Kaczynski may well say "no" even if offered a fully working Trident D5. Some
      • by Vellmont ( 569020 ) on Sunday January 25, 2009 @03:36PM (#26600739) Homepage


        Besides, a lot of the difficulty in making even an inefficient nuclear bomb at all obtaining the weapons grade fissile material.

        I'd say that the vast majority of the difficulty is obtaining the fissile material. Weapons grade uranium/plutonium doesn't exactly grow on trees. Creating it yourself (and preventing anyone from stopping you) takes the power of a government.

        This has essentially been the policy to control proliferation for 60 years now. Stopping the knowledge of the design details is merely security theater.

        • Weapons grade uranium/plutonium doesn't exactly grow on trees

          Unless you live near 3 Mile Island!

      • by vlm ( 69642 )

        The simple facts are that he (a truck driver!) is collecting detailed information about some of the worlds least efficient nuclear bomb designs.

        Besides, a lot of the difficulty in making even an inefficient nuclear bomb at all obtaining the weapons grade fissile material.

        Maybe a better way to summarize his work vs "the real thing" would be a different analogy:

        It's like comparing a guy who enjoys collecting pr0n vs actually reproducing with a supermodel.

      • Re: (Score:3, Insightful)

        by khallow ( 566160 )

        No terrorist orginaization would want to create such wasteful bombs

        Article said it required about eight times critical mass. That's not bad for something you don't need to test first. Besides the design was good enough for the US to make first. Keep in mind that if you are committed to the terrorist act of blowing up an innocent city with a fission bomb, then you've divorced yourself from usual considerations of efficiency.

      • by T5 ( 308759 )

        No terrorist orginaization would want to create such wasteful bombs, so the information he is publishing is not very dangerous at all.

        Dead wrong. Any sufficiently funded terrorist organization is the only market for such an antiquated device. No government would want to field one of these (N. Korea excepted), but any terrorist/extremist group would give their last item of worth for just one of these. Terror does not require efficiency.

    • Comment removed (Score:5, Informative)

      by account_deleted ( 4530225 ) on Sunday January 25, 2009 @03:15PM (#26600561)
      Comment removed based on user account deletion
    • Re: (Score:3, Insightful)

      that's just the way our society has come to think. in most people's minds (including many regular citizens) the masses are simply too stupid, selfish, immoral, and irrational to be treated as mature & rational adults and allowed to govern themselves. therefore they must be ruled over by others who are more trustworthy and level-headed, which coincidentally are the rich & powerful. and following this kind of thinking, information that can potentially be used for evil must necessarily be suppressed an

    • Re: (Score:3, Informative)

      by rubycodez ( 864176 )

      eh, most students don't know "critical mass" for a spherical shape of uranium of given enrichment, that's actually a pretty hairy calculation. Pure U-235's value is published but who outside of a hard care geek is going to remember it? And as for a "pile", of blocks of fissionable material and moderator and support structure, I've a big thick textbook on that subjects, ain't easy at all.

  • by pjt48108 ( 321212 ) <{mr.paul.j.taylor} {at} {gmail.com}> on Sunday January 25, 2009 @02:56PM (#26600401)

    This is yet another example of things which, eight years ago, might have seemed merely odd, rather than somewhat unsettling.

    How quaint the 20th Century already seems.

    • by Wes Janson ( 606363 ) on Sunday January 25, 2009 @07:02PM (#26602409) Journal
      It's only unsettling to those who are uneducated in the subject. Anyone with a passing knowledge of nuclear weapons can tell you why this is completely irrelevant from a security perspective. And anyone who pays real attention can tell you what you should really be worrying about.

      Unfortunately, the percentage of Americans who have even that passing familiarity with nuclear weapons is probably no greater than 2 or 3 percent. Which means 97-98% of the population is going to react out of fear, uncertainty, and doubt in anything related to the matter.
  • Not so big a deal (Score:5, Informative)

    by Ancient_Hacker ( 751168 ) on Sunday January 25, 2009 @03:09PM (#26600521)

    The Hiroshima bomb was a very simple "gun" design. Plenty of published info on it. It used a navy gun barrel cut down to size, a U235 doughnut target, a polonium initiator, and a U235 projectile. Mighty simple. Any chopper shop could build one, with the exception of getting the Polonium and U235.

    This design was abandoned as it had many drawbacks-- it used about 8 times more U235 than absolutely necessary, there was a 7% chance of a fizzle, and there was no way to make it safe.
    But it had the advantage that it was dead-simple and guaranteed to work, well 93% of the time.

    Now if he made a replica of Fat Man, that would really be something.

    • Re:Not so big a deal (Score:5, Informative)

      by Compholio ( 770966 ) on Sunday January 25, 2009 @03:15PM (#26600565)

      ...a U235 doughnut target, a polonium initiator, and a U235 projectile...

      If you'd actually read the article then you'd know that he discovered that the projectile was hollow and the target was solid. Personally, I just skimmed it - but it seems like he collected a lot of facts that lead him to believe that people were parroting incorrect information about how the bomb was constructed and he wanted to set the record straight.

    • Re:Not so big a deal (Score:5, Informative)

      by RDW ( 41497 ) on Sunday January 25, 2009 @03:23PM (#26600627)

      'The Hiroshima bomb was a very simple "gun" design. Plenty of published info on it. It used a navy gun barrel cut down to size, a U235 doughnut target, a polonium initiator, and a U235 projectile. Mighty simple.'

      A major point of the article is that many of the key (and repeatedly published) 'facts' about the bomb are quite wrong. e.g., according to Coster-Mullen, the projectile was actually a hollow cylinder and the target was a rod rather than a doughnut - 'little boy was female'. Wikipedia is now using his version of the bomb design in the Little Boy article:

      http://en.wikipedia.org/wiki/Little_Boy [wikipedia.org]
       

      • Re: (Score:3, Interesting)

        Well a cylinder and rod sound like a really poor design. You want a quick transition to super-criticality, not a slow linear slide. Much more likely they were a conical target and a mating projectile.

          Maybe this guy is trying to disinform certain rogue scientists?

        • It's about the mass (Score:5, Informative)

          by DG ( 989 ) on Monday January 26, 2009 @06:34AM (#26605855) Homepage Journal

          Actually, it is a pair of nested cylinders, and the rationale behind it is brilliant.

          To get the biggest possible boom, you want to bring together the largest possible mass of fissile material. Problem: if you accumulate too large a mass, it starts a chain reaction on its own.

          But if you form that mass into a ring shape, and make the hole in the ring large enough, you create extra surface area for neutrons to escape, but the gap is too big for them to have sufficient energy to split an atom on the other side of the gap.

          For a given outer diameter (fixed by the inner diameter of the bomb casing) the maximum mass of fissile material is obtained with a cylinder whose height is determined by the mass on the "side" of the cylinder nox exceeding criticality. A mating cone shape results in a smaller usuable mass.

          So why make the projectile hollow instead of shooting a slug into a hollow target? Because the sides of the gun barrel constrain the movement of the projectile and ensure that the mating surfaces are aligned.

          It's actually, for such a "crude" design, brilliant engineering.

          DG

          • by goodmanj ( 234846 ) on Monday January 26, 2009 @09:19AM (#26606861)

            the gap is too big for them to have sufficient energy to split an atom on the other side of the gap.

            This can't be right. The area inside the ring is filled with air, right? Neutrons go through a few cm of air like it's not even there.

            Besides, to prevent a chain reaction, you need to reduce the odds that an average fission neutron will collide with and split another U nucleus. Reducing the energy of those neutrons doesn't help -- in fact, it generally *increases* the odds of causing fission, which is the point of moderators in nuclear power plants.

            Your point about conical geometry reducing the total possible fissile mass is a good one, but I wonder if there's some intermediate shape, like a hyperboloid, that might give a better trade-off between collision time and fissile mass.

    • by Detritus ( 11846 )
      According to the article, the projectile had a hollow center, and the target was a cylinder that fit inside the hollow center of the projectile. That's the opposite of most descriptions of the weapon.
    • His book also contains a exact engineering description of Fat Man.

  • by sphealey ( 2855 ) on Sunday January 25, 2009 @03:24PM (#26600631)

    One thing to keep in mind when you read statement such as "Destroy R. Worlds, former Director of Bomb Design at Los Alamos, said of Joe Amateur's work 'That's very well-done'" is this: reading between the lines of many interviews, articles, and books about and by former weaponeers they give out a lot of misleading, and/or misdirecting, information about how _exactly_ devices are built. They talk openly about the general principles and their scientific and political implications, but when the discussion/interview/chapter turns to the actual details of design, well, the replies turn a bit fuzzy or clever. I suspect that either by explicit training or shared values they give away very little and much of what they say would deliberately lead anyone following down the wrong path.

    sPh

  • Pictures? Plans? (Score:3, Interesting)

    by nurb432 ( 527695 ) on Sunday January 25, 2009 @03:52PM (#26600869) Homepage Journal

    Its got some abstract image and a story.. But where is the actual scientific meat?

    Oh, thats right, knowledge is forbidden in this country.

  • by dd1968 ( 1174479 ) on Sunday January 25, 2009 @04:00PM (#26600953)
    From the article: "Actually, he said, nothing about the bomb is secret. He smiled and added, 'The secret of the atomic bomb is how easy they are to make.'"
  • http://www.atomicmuseum.com/store/ProductItem.cfm?Category=179 [atomicmuseum.com]

    TFA said he uncovered that the Little Boy diameter was 28" rather than 29" - so, I'm not speaking for the accuracy of these blueprints - just letting people know that they're out there.

    Frankly, from the account given in the article of the hissy fit that he threw when at the museum in Albuquerque, I wonder about the guy. The museum's always been pretty cool, and back in 93 when he visited it, it was at KAFB. The docents and staff have always bee

  • by Iamthecheese ( 1264298 ) on Sunday January 25, 2009 @09:21PM (#26603433)
    Somebody set up us the bomb!
  • by n6kuy ( 172098 ) on Monday January 26, 2009 @12:35AM (#26604551)

    ... of both Fat Man and Little Boy.

    See here [lanl.gov], for example.

    • Re: (Score:3, Informative)

      by n6kuy ( 172098 )

      Although that Little Boy replica at Los Alamos might not be as accurate as the previous one they used to have. See here [lanl.gov].

news: gotcha

Working...