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Dear Keiva: But what could they have used to achieve safe but dependable spontaneous ignition? I have wondered if elemental phosphorus could do it, but can't imagine their being able to prepare it or store it.
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Again, I'm speculating, dr. bill.
You want the chemical to ignite easily when it reaches the enemy, and yet remain stable in the weeks before then while you are sailing to meet him. That would be solved by a binary process, by which there is no instability until the two parts are mixed.
The remaining problem is to keep the chemical stable in the few seconds after you've mixed (preparatory to firing) but before you fired it. One answer: fire off the two parts of the binary separately, so that they don't "mix" until they each hit the other ship or the water surrounding it. Another possibility: if the chemical remains stable (though barely) even when the binary parts are mixed, then you can mix it and hurl it onto the other ship, and then ignite it there by use of a flaming arrow.
But again, what I write here is purely speculative.
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Phosphorus was first isolated in 1669. One source I've seen suggested metallic sodium, potassium, or lithium, but as these weren't isolated till the early 1800s...
Hm, plenty of websites taking in each other's washing by mentioning the same lists of flammable ingedients, and the methods of delivery (clay grenades as well as pumps or tubes), but I haven't found anything yet that addresses this stability problem.
Perhaps it ignited on contact with water?
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Dear NicholasW: please consider authenticity of encyclopedia account:
Greek Fire, a gelatinous, incendiary mixture, used in warfare before gunpowder was invented. Flammable liquids had long been in use, but it was not until the 7th century that Greek fire was invented, possibly by Callinicus, an Egyptian architect who had fled from Syria during the Muslim invasions. Greek fire was an effective weapon, especially when used against ships at sea. The substance apparently ignited spontaneously, and could not be extinguished by water. In 673 Greek fire was used by the Byzantine Empire to repel an Arab fleet attacking Constantinople (present-day Istanbul); the Byzantine Empire continued to use Greek fire in combat until the empire's fall in 1453.
The formula of Greek fire was closely guarded as a state secret for many centuries by the Byzantine Empire. The exact composition of Greek fire is still disputed, but it was probably composed of a mixture of flammable materials such as sulfur and pitch in a petroleum base. This jellylike mixture was sprayed on the enemy from tubes through which it was forced under pressure by pumps.
"Greek Fire," Microsoft(R) Encarta(R) 98 Encyclopedia. (c) 1993-1997 Microsoft Corporation. All rights reserved.
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That's what I meant, they all have variations of this, but that account doesn't suggest how it ignited, whether by contact, time, pressure, catalysis, or what.
There's a contemporary picture that shows fire spurting out of the barrel, i.e. it was on fire as soon as it entered the air. I don't suppose we need rely on that picture, but it doesn't look like twin tubes. A binary would be easier in grenades, but it doesn't look like it was fired as a binary.
Could a mixture be flammable in the open air and non-flammable under confinement, so that they could light it at the nozzle as it sprayed out and not have it blow up the barrel?
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Dear NicholasW: I wonder how good pumps they had. A really good pump can convert enough work into heat to give one a blister. If one puts a finger over air outlet of a bicyle pump, pushes plunger to get maxixmum pressure, and then allow a small air leak, there is enough heat released to be quite painful. A mixture with both naphrha and sulfur might have low flash point. A modern flame thrower has to have some kind of an igniter. I wonder if Greeks had any think like punk that could burn slowly enough to last until it was needed, to ignite the stream of the flammable materials.
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Could a mixture be flammable in the open air and non-flammable under confinement?
Yes, but that wouldn't do the job. To store such a mixture safely, it would have to be kept in an absolutely airtight container, and it would have to absolutely fill that container (with no air space at the top). I suspect htat's not practical -- and with the slightest goof you'd have a fire on your own ship.
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The exact composition of Greek fire is still disputed, but it was probably composed of a mixture of flammable materials such as sulfur and pitch in a petroleum base.
In other words, prototypical napalm. Great stuff. Works best on helpless civilians. Ask the Vietnamese.
The idiot also known as Capfka ...
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