Tucker: I got a modem, too. Quitcher bitchin.
(Stop it. Stop right now! This is getting silly.)
G’day
Here are some clear examples:
The technology for producing a purple patina on bronze was known in Classical times, lost in the Middle Ages, and recently recreated.
The technology for producing so-called ‘Damascus Steel’ was known in mediaeval India, but was lost. There have been several claimed re-creations of this technology.
The technologies for producing and rowing the classical galleys called ‘triremes’ and ‘quinquiremes’ were lost in Roman times (a possible consequence of the introduction of catapults at sea). There used to be a heated controversy among historians about several basic issues, but now that several reconstructions have been built and rowed we seem to be conveging on agreement about the basics: how many banks of oars, how many rowers per oar, what a rower’s ‘cushion’ was made of and what he wore it for, etc.
So it certainly seems possible to lose individual items of technology, but perhaps a case could be made that those above are all cases in which technologies were abandond because they had become obsolete.
Perhaps the most fascinating example is the loss of the ability to make fishhooks and to fish by the indigenous people of Tasmania. For unknown reasons, about 3500 years ago, Tasmanians stopped making fishhooks, fishing, eating fish. They were still not doing so in the early 19th Century, though the fish were (by that time at least) perfectly wholesome.
Regards,
Agback
I’m going to ask you to check your facts: not because I think anyone is quite certain how the Egyptians assembled a pyramid, but because I’m pretty certain that Old Kingdom Egypt had few slaves.
Last I heard the pyramid-building worker’s villages have been excavated, and the signs are that the workers were a mixture free and high-status specialists together with peasants doing their tribute-labour during the season when their was not work in the fields.
It’s funny that this has come up now, because only last week on a mailing list I saw an argument in which a fellow cited Exodus as evidence for the existence of a large population of slaves in ancient Egypt, and got slapped down by the arkies.
Regards,
Agback
You can certainly find lists of ingredients, but most of them are speculative. In some cases the speculations are quite old (15th century), but even so none of them works the way Greek Fire was supposed to work. But then, given that our records of what Greek Fire did are based on rumours heard by French monks who never came within 1,000 km of any Greek Fire, perhaps Greek Fire didn’t work that way either.
More: the ingredients aren’t the end of the story, because some documents suggest that Greek Fire was projected, in the form of a je of burning liquid, our of an apparatus. We don’t know how the apparatus was made or used. That as much as the recipe is the lost technology of Greek Fire.
Regards,
Agback
Einstein, when asked of which of his contributions were not possible without him, he thought for a long time before replying, “General Relativity.”
I am not so sure. Granted, Einstein was one of the best if not the best physicists ever, he was aide by the fact that he was at the right place at the right time.
I suspect somebody such as Hawking can very well come up with GR on his own.
Urban Ranger: Agreed that the evidence was in front of everyone’s noses, but how many would have come to the initially illogical but completely supported conclusion Einstein did? The concept of the speed of light in a vacuum being a constant and everything being relative to that is not an extension of classical physics. In fact, it attacks the foundation of Newtonian mechanics by killing the notion of the absolute. Mass-energy equivalence, gravity as space-time curving, and all of the rest were supported by physical evidence and the equations, but the idea of frames of reference, all equally vaild but none quite agreeing on anything but the velocity of light, was the stroke of genius it took an Einstein to see.
I should clarify: It attacks the notion of the absolute observer standing in the only correct frame of reference. It creates a new absolute in the form of the speed of light in a vacuum.
It’s not just amateur telescope makers that hand-grind lenses. Lens grinding is still done at optical firms and by the folks who make molds for plastic optics. It’s not as big business as it was, but it still hasn’t been completely wiped out by diamond-turning and other technologies.
I vaguely remember reading someplace (which is the cue for better-informed Dopers to either confirm or shoot it down) that NASA has a fair number of data tapes with stellar observations recorded in the 60’s moldering in storage because they no longer have the machinery to read them. An apocryphal tale?
Also, many magicians go to their graves with their secret techniques of prestidigitation unrevealed. I don’t know if that strictly qualifies under the terms of the discussion, but it is an interesting tangent.
Cervaise, I don’t know about NASA, but I do know that one university put tons of data on tapes that no one has the machines to read anymore.
Oh, and Ringo, I’ve found two recording studios which advertise that they have analog tape decks. One is Real World Studios which is owned by Peter Gabriel, and the other is Cue Recording, and I found these after the most casual google search. Additionally, it occured to me that if there were no analog tape machines in use, there’d have been an article in one of the recording industry trade magazines discussing “the death of analog recording.”
Technologies we’ve lost tend to have to do with crafts that for some time were not valued. There are important ceramics and glass techniques that are no longer known.
As to the Saturn plans (speaking as a long time ex-NASA contractor) the common wisdom was that they were destroyed as a part of house cleaning. Remember, this was the pre-personal computer days, and the plans were hardcopy, and taking up lots of space. At the time, dear old president N**** assured us that they wouldn’t be needed any more, since he was going [official lie follows] to aggressively fund the next generation of launch vehicles.
Cervaise, you may be quoting me about NASA tapes which are no longer readable. I wrote something awhile ago about the room in our basement filled with moon-related tapes that probably can’t be read anymore. The guy from JPL who did the early composite shot of Jupiter (Saturn?) moons told me 10 years ago that the tapes he checked from early lunar missions were so far decomposed that the surface fell off the backing medium when they were loaded.
Natural rubber is still highly valuable–natural, vulcanized rubber is used on airplane tires, because it’s tougher (more highly cross-linked) than artificial rubber.
Not to cast aspersions, partly, but there was a thread on the boards some time back where another Doper stated that the original Saturn V plans are still around. I’ve also got an article around here in either a Smithesonian or Air & Space magazine which discusses the cosmetic restoration and might mention something about the plans. However, I am too tired to flay hamsters or tear my place apart to find the magazine. I would like to see, sometime the official government document which states that either the plans were destroyed or that they are currently located in ______, so that this matter can finally be put to bed. (I’m hoping that they’re still around so that we can all do a collective “neener, neener” to Richard Hoagland who says they’ve been destroyed.) IAC, I’d just like to add that some people hate Nixon for Watergate, I hate him for what he did to NASA. :mad:
Ringo: The rheostat in motion picture projectors is a good example of a “lost” technology that isnt particularly lost, just outmoded and no longer used. Since the advent of sound-on-film, film speed was standardized to 24fps (so the sound would reproduce accurately). Silent movies didn’t have to worry about such things, and the projectionist was sometimes as much a part of the movie as the filmmaker, as he merrily sped up or slowed down the film speed as he thought fit. Or let it run as the cameraman had intended it. This is why the Keystone Cops move fast even at silent speeds and love scenes go slow. I don’t know if they still make them, but when I was taking film classes, silent films were projected on a Seimens (sp?) projector, which had two reels (one for sound, one for image) and could be varied.
Another example of a ‘lost’ technology was Clovis arrowheads, but iirc that technique for making sharp flint was rediscovered recently.
<nitpick> A Clovis point mounted on an arrow would fly about 10 feet and then drop. These points are representative of the earliest known culture in North America (12-15k BP depending on who you ask and which sites you are looking at), predating bow and arrow technology, in any case, by thousands of years. They are typically referred to simply as a fluted point. </nitpick>
Additionally, there are some practitioners who posess the ability and technology to make them. However, there is some discrepancy around as to how the points were fluted as differenct practitioners have done it in several different ways.
In New England, starting (IIRC) in the 1960’s, people started to preserve and restore old covered bridges. Unfortunately, no one really knew how to build them anymore. Some timber framers found some old timers who had worked on them way back when and recreated the art. Now there are a small number of folks who restore old bridges and build completely new ones.
I suppose it would have been possible to recreate a bridge using an old one as an example without any other knowlegde, but you’d just be recreating copies, not performing the same design and construction techniques.
Oh, no offense taken. I didn’t work at a center that developed the plans, I just heard rumors from the grapevine. There are a number of reasons I doubt the original plans exist, at least not all of them. But they’re’d be no purpose to reviving the Saturn at this point. The Russian engines we’re using now are far more sophisticated. Materials have moved on. So, it’s not really “lost” technology, in a sense.
Actually, the Soviets relied on vacuum tube technology for strategic reasons, not because they couldn’t develop more modern systems. When the first Soviet jets using tubes were examined, Western sources ridiculed the “backwards” Soviets. But several years later, NATO realized that if there had been a general war with the Warsaw Pact and nuclear weapons had been used, many of their planes would have been disabled by the resulting electromagentic pulses. Vacuum tubes are unaffected by EMP and the Soviet planes would have kept working.
You’re right about vacuum tubes not being affected by an EMP, but I’m not so sure about saying that the Soviets stuck with tubes for that reason. I know that they copied an old IBM wire-frame computer and kept the known glitches in the design even though they could have easily corrected them. Ever heard of the Trabant? It was supposed to be the Communist Bloc’s answer to the VW Beetle. As I’m sure numerous of our European Dopers can testify, it was an unmitigated piece o’ crap that is rapidly proving to be a disposal problem in a post-Soviet world (something about toxic material being used in the body panels, IIRC). If the Communists couldn’t duplicate the Model-T (which by all standards was a vastly superior car to the Trabant) some thirty to forty years later, why should we expect them to come up with something as complicated as a decent integrated circuit? Everything I’ve read has indicated that the Soviets never mastered the task of building intergrated circuits to the level necessary for military purposes.
I know that this thread died off, but someone revived so I’ll use it to get stuck into Duh!Leth. Urban Ranger referred to general relativity. Duh!Leth’s remarks confuse general and special relativity. Do you, Duh!Leth grasp that Einstein posited two theories of relativity?
Special relativity does indeed “attack the foundation of Newtonian mechanics”, but this “attack” originated in the work of James Clerk Maxwell. The time dilation, length contraction, etc. equations are all due to Lorentz. If Einstien hadn’t come up with special relativity when he did, someone else would have shortly afterwards.
What you have gotten completely ass-backwards is the “Mass-energy equivalence, gravity as space-time curving” thing. That’s general relativity, and it wasn’t “supported by physical evidence and the equations” or anything else.
General relativity is why Einstein is regarded as a genius by physicists and mathematicians. Special relativity is why Einstein is remembered by school kids.