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User: jgmaynard

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  1. Re:Taking Their Sweet Time on China to Land on Moon Around 2017 · · Score: 1

    The other thing entering into this is that the value of Chinese Yan is tied to the U.S. dollar - it's not an independently valued currency.... JM

  2. Re:Taking Their Sweet Time on China to Land on Moon Around 2017 · · Score: 1

    NASA doesn't even know how to do it with 1960's tech at all... ALl the plans for the Saturn Five were destroyed after the program ended. Besides, who would want to use the 1960.9 distro? lol JM

  3. Re:Eric Lerner on Alternative to Tokamak Fusion Reactor · · Score: 1

    VERY good, Eric...... A nice explanation..... Kudos! JM

  4. Re:erm.. on 5 Years of Habitation on the ISS · · Score: 1

    We could just wait three years and just buy them tickets on Virgin Galactic. :) I'm willing to bet that Burt Rutan gets a man on Mars before NASA gets another man on the Moon...... Anyone want to take that bet? JM

  5. Re:well, actually... on Dawn's First Light · · Score: 1

    Electromagnetic waves or em radiation is even better! lol JM

  6. Re:Roman navies. on Archimedes Death Ray in San Francisco · · Score: 1

    Yes, the Roman navies were mostly temporary - The Romans were never a natural sea-faring people, and when they did get a good navy, it was by copying the design of a Carthaginian ship during (IIRC) the Second Punic War. Of course, the Battle of Actium was the last time that the Roman Navy was used en masse, most of the ships being retired by Augustus soon afterwards. But the device those fellows built to "replicate" Archimedes machine was way different - They bult it with glass mirrors which would not have been available to Archimedes, and they also focused the light from about one meter away, whereas Archimedes weapon was said to set boats on fire at a distance of thirty kilometers... That's a HUGE difference! So, in my book I came to the conclusion that Archimedes made some incredible weapons to defend Syracuse, but the death ray was not one of them........ JM

  7. Re:Archimedes other weapons on Archimedes Death Ray in San Francisco · · Score: 1

    Are you sure they weren't sea bass? LOL From my book in the chapter about Archimedes because I am TDL to type it all again: Perhaps the most remarkable of the war machines of Archimedes was his steam cannon. This looked like a civil war cannon, with two noticeable exceptions. The first was two pieces of wood, one that ran down the length of the barrel, holding the ball in place and the second piece of wood sat at right angles to the first piece, held against the mouth of the cannon by two metal brackets. The second difference had to do with the propulsion method, since ancient Mediterranean people did not have gunpowder. There was a water tank and valve above the breech of the cannon and a fire underneath it. The fire would burn until the metal was red hot and then the valve was turned, allowing water into the breech. Pressure was built up behind the cannonball until the wood at the front of the cannon broke into two pieces, shooting the cannonball out with a tremendous force. JM

  8. Re:The other thing to remember on Archimedes Death Ray in San Francisco · · Score: 1

    It was certainly possible that for this use Archimedes may have used metal, but the mirrors for everyday use in Greece and the Roman Republic (roughly) were usually malachite, or one other material which escapes me right now - it might even be a metal... And metal is shiny, but I doubt it has the reflective ability to reflect enough light to set a ship on fire from the sixty km (?) usually claimed. I'll wake up at 3am with the answer and post it.... :D JM

  9. Re:flammability differences on Archimedes Death Ray in San Francisco · · Score: 1

    It is said that Caesar set the ships of Ptolemy XIII on fire in the Alexandrian port, and that this was the first of the events leading to the downfall and destruction of the Great Library of Alexandria.
    But it's also interesting to me that Caesar wrote a book on the subject ("The Alexandrian War") and he makes no mention of it, and neither does Cicero, who could... not... stand... Caesar. You would think if such a destruction took place, it would have been told of by Cicero at least (Caesar himself wrote one-sided accounts).
    My point is, yes, ships were set on fire in the ancient world as a method of warfare, but it is iffy (as I understand) whether the most famous one in history actually occured... JM

  10. Re:Was it ra really sunny day? on Archimedes Death Ray in San Francisco · · Score: 1

    "consider that Greece lies in part of the world getting a lot of sunshine. If they want definitive result, they should match try it near the place Archimedes did it." I know it's nit-picking, but..... This machine was supposedly built for the defense of Archimedes' home city of Syracuse, which is in Sicily, not Greece. About thesame latitude, but just wanted to make sure we were all on the same page... JM

  11. And then there was.......... on Tropical Storm Alpha Sets Naming Record · · Score: 1

    Hurricane Omega. Now that would be scary! LOL Sings: It's the end of the world as we know it........ LOL JM

  12. Resistance is futile on Cyborg Cells Sense Humidity · · Score: 0

    Resistance is futile.......... LOL Actually, it's funny that someone mentioned the beginning of the Borg... I've had an idea running through my head for a couple of years about exactly that...... :) JM

  13. The other thing to remember on Archimedes Death Ray in San Francisco · · Score: 5, Informative

    Hi.... It's my first post here..... I really like this site! Now.... The other thing to remember is that at the time of Archimedes, good quality glass was not discovered yet - most mirrors at the time were made from malachite. Such a mirror would not have reflected nearly the amount of light that a modern glass mirror would have done. Good quality glass did not come into Rome until about 250 years after Archimedes. I actually looked into this pretty carefully for my book "The Light of Alexandria" - http://www.lightofalexandria.com/ . Some of the other inventions that Archimedes made for the defense of Syracuse were pretty amazing, though........ JM