Greek Fire
Alexander Bowne
The secrets of Greek fire would be useful even in the modern world, so it is not surprising that people continually try to determine its composition. What is surprising is the fact that we haven't, to our knowledge, determined exactly what was in it. There are theories with supporting evidence as to some of its ingredients, however, and three of those theories likely hold water (on fire or otherwise).
The leading theory in modern times is that the base of Greek fire was a petroleum based mixture, similar to modern napalm. The Byzantine Greeks would have had access to at least crude oil, so it is not unrealistic to think that they may have refined it in some manner. This would also help explain why Greek fire was not replicated elsewhere contemporaneously, since not all countries or locations would have had ready access to crude oil, at least not without modern drilling and refinery techniques. Its similarities to modern napalm would also help explain why it burned for so long and was so "sticky."
Another probable ingredient is resin or resins from various trees. This would have been used largely as a thickening agent and to increase the sticky factor. Surviving descriptions of Greek fire generally describe a substance thicker than simple refined petroleum, so it makes sense to include a sticky, flammable thickening agent.
Finally, I posit that quicklime (calcium oxide) was included. Many modern theories exclude quicklime as a possibility, but humans have known how to make quicklime for thousands of years, and its extreme reaction with water would help explain why we mostly hear of Greek Fire being used at sea, where even "dry" decks would have enough water to activate the Greek Fire.
Obviously, this is all estimation, as I have not yet personally discovered the actual components of Greek fire. However, all of the components would have been available to the Greeks and would combine to create one fearsome weapon, Greek fire or not.
Sources: http://www.britannica.com/EBchecked/topic/244571/Greek-fire, http://en.wikipedia.org/wiki/Greek_fire
The leading theory in modern times is that the base of Greek fire was a petroleum based mixture, similar to modern napalm. The Byzantine Greeks would have had access to at least crude oil, so it is not unrealistic to think that they may have refined it in some manner. This would also help explain why Greek fire was not replicated elsewhere contemporaneously, since not all countries or locations would have had ready access to crude oil, at least not without modern drilling and refinery techniques. Its similarities to modern napalm would also help explain why it burned for so long and was so "sticky."
Another probable ingredient is resin or resins from various trees. This would have been used largely as a thickening agent and to increase the sticky factor. Surviving descriptions of Greek fire generally describe a substance thicker than simple refined petroleum, so it makes sense to include a sticky, flammable thickening agent.
Finally, I posit that quicklime (calcium oxide) was included. Many modern theories exclude quicklime as a possibility, but humans have known how to make quicklime for thousands of years, and its extreme reaction with water would help explain why we mostly hear of Greek Fire being used at sea, where even "dry" decks would have enough water to activate the Greek Fire.
Obviously, this is all estimation, as I have not yet personally discovered the actual components of Greek fire. However, all of the components would have been available to the Greeks and would combine to create one fearsome weapon, Greek fire or not.
Sources: http://www.britannica.com/EBchecked/topic/244571/Greek-fire, http://en.wikipedia.org/wiki/Greek_fire
Angel Pevensie
Greek Fire was the secret weapon of the Eastern Roman Emperors. It is said to have been invented by a Syrian Engineer, one Callinicus, a refugee from Maalbek, in the seventh century (673 AD). The "liquid fire" was hurled on to the ships of their enemies from siphons and burst into flames on contact. As it was reputed to be inextinguishable and burned even on water, it caused panic and dread. Its introducation into warfare of its time was comparable in its demoralizing influence to the introducation of nuclear weapons in our time. Both Arab and Greek sources agree that it surpassed all incendiary weapons in destruction. The secret behind the Greek fire was handed down from one emperor to the next for centuries. Rumors about its composition include such chemicals as liquid petroleum, naphtha, burning pitch, sulphur, resin, quicklime and bitumen, along with some other "secret ingredient". The exact composition, however, remains unknown.
Although the presence of either quicklime or saltpeter in the mixture cannot be entirely excluded, they were consequently not the primary ingredient. Most modern scholars agree that the actual Greek fire was based on petroleum, either crude or refined; comparable to modern napalm. The Byzantines had easy access to crude oil from the naturally occurring wells around the Black Sea or in various locations throughout the Middle East. An alternate name for Greek fire was "Median fire", and the 6th-century historian Procopius, records that crude oil, which was called naphtha by the Persians, was known to the Greeks as "Median oil". This seems to corroborate the use of naphtha as a basic ingredient of Greek fire. Resins were probably added as a thickener, and to increase the duration and intensity of the flame. A modern theoretical concoction included the use of pine tar and animal fat along with other ingredients.
Although the presence of either quicklime or saltpeter in the mixture cannot be entirely excluded, they were consequently not the primary ingredient. Most modern scholars agree that the actual Greek fire was based on petroleum, either crude or refined; comparable to modern napalm. The Byzantines had easy access to crude oil from the naturally occurring wells around the Black Sea or in various locations throughout the Middle East. An alternate name for Greek fire was "Median fire", and the 6th-century historian Procopius, records that crude oil, which was called naphtha by the Persians, was known to the Greeks as "Median oil". This seems to corroborate the use of naphtha as a basic ingredient of Greek fire. Resins were probably added as a thickener, and to increase the duration and intensity of the flame. A modern theoretical concoction included the use of pine tar and animal fat along with other ingredients.
Ariella McManus
There is a reason it is called 'secret'. Though there has been much conjecture, no one can say with 100% accuracy exactly what made up the important 'ingredient' list in the 'recipe' for Greek Fire. However, given the nature of the reaction and what history has taught us of the time period, it is possible to narrow it down to a list of likely candidates. I have, therefore, after doing a little research, come up with a list of the most common ingredients and will attempt to explain why I believe them to be feasible.
One possible ingredient is quicklime, the 'common name' for calcium oxide. Although there has been some speculation about this particular ingredient, I would opt for the opinion that it makes perfect sense for it to have been used. It is highly reactant with water, and upon contact, can raise its temperature above 150 degrees C, thus making it possible to ignite the fuel source. On the open waters, it could have added to the veritable 'sea of fire' effect that Geek Fire was so infamous for..and one reason it was so feared.
Research also brought up saltpeter, and there are several camps of thought on this one. I can appreciate where its history as a ingredient in explosives makes saltpeter (or sodium nitrate if you want to be scientifically accurate) a likely candidate, but if one goes along with the school of thought (as I am inclined to do) that refined saltpeter was not readily available in the West until well after 1125, it makes it rather improbable. To be fair, impure saltpeter could have been harvested for use , so there is that possibility. Saltpeter is a component in gunpowder, so one could argue, I suppose, that Greek Fire is a precursor to modern-day gunpowder.
Bitumen is a sticky, black, highly viscous solid or semi-solid found in petroleum based substances, and there is every reason to believe that Greek Fire was indeed petroleum based. The Byzantines had easy access to petroleum (or crude oil, if you will) from areas such as the Black Sea or various other places in the Middle East. Bitumen (the 'sticky' part such as tar) which was also commonly used as waterproofing for ships, would have aided in the 'staying power' of the flames and helped increase their spread. Basically speaking, it would have acted like a natural fire trap, keeping the flames concentrated and allowing the quicklime and saltpeter to do their work of increasing the temperature
Sulphur, otherwise known as brimstone, is another 'must have' in the list of ingredients. Sulphur is commonly found around volcanic regions, and historically, one such area was smack-dab in the middle of the Byzantine Empire, namely the area known as Cappadocia. Thus, the ingredient was not only easily obtainable, but its properties make it a definite key element. Not only does sulphur act as an oxidizer, this bight yellow soft solid increases when in liquid form and is highly flammable. Can we say BOOM?!
I have already mentioned crude oil (or petroleum), now let me get a bit more specific. I am speaking of naptha. Interesting enough, coal tar can be broken down to produce naptha, and as we have already seen, bitumen (or tar) is an ingredient in our 'mix'. Coincidence? I think not. It can also be extracted from wood, and given that this was a maritime society, well, it makes perfect sense if you ask me. It is highly volatile and insoluble in water. Again, can we say..KABLOOEY?!
Next on our list is tartar. This is an ingredient in the making of potash (or potassium carbonate for the scientifically snooty among us). It acts as a 'lightning rod' or electrolyzer when it comes in contact with water. One can only imagine how this would work in conjunction with the catalysts and bases we have already mentioned. Easily mined from water-soluble salts, it would have been quite easy to obtain. Salts..ocean...get the connection?
Last, but most decidedly not least is the 'glue' to bind it all together..namely resin or pitch. Pitch can be made from either plant based sources (in which case it is called resin) or our old friend petroleum (in which case it is called..tada..bitumen (or pitch..so sue me, I was going for the dramatic flair). One interesting tidbit I ran across in my research was mention of a specific plant called sarcocolla, a small shrub native to Southern Africa, and the sticky substance derived from it. Given the vast spread of the Byzantine Empire and the 'duty' of pitch in the 'recipe', I would hazard to believe that this particular plant may have been harvested a time or two for such a purpose. It should also be noted that some resins contain heptane, which are highly explosive and flammable.
And there you have it, the 'recipe' for Greek Fire. Though we cannot know for certain if it is the original (or even if it would work at all), given the properties of the ingredients I have found, I would be willing to bet a coin or two in its favor.
One possible ingredient is quicklime, the 'common name' for calcium oxide. Although there has been some speculation about this particular ingredient, I would opt for the opinion that it makes perfect sense for it to have been used. It is highly reactant with water, and upon contact, can raise its temperature above 150 degrees C, thus making it possible to ignite the fuel source. On the open waters, it could have added to the veritable 'sea of fire' effect that Geek Fire was so infamous for..and one reason it was so feared.
Research also brought up saltpeter, and there are several camps of thought on this one. I can appreciate where its history as a ingredient in explosives makes saltpeter (or sodium nitrate if you want to be scientifically accurate) a likely candidate, but if one goes along with the school of thought (as I am inclined to do) that refined saltpeter was not readily available in the West until well after 1125, it makes it rather improbable. To be fair, impure saltpeter could have been harvested for use , so there is that possibility. Saltpeter is a component in gunpowder, so one could argue, I suppose, that Greek Fire is a precursor to modern-day gunpowder.
Bitumen is a sticky, black, highly viscous solid or semi-solid found in petroleum based substances, and there is every reason to believe that Greek Fire was indeed petroleum based. The Byzantines had easy access to petroleum (or crude oil, if you will) from areas such as the Black Sea or various other places in the Middle East. Bitumen (the 'sticky' part such as tar) which was also commonly used as waterproofing for ships, would have aided in the 'staying power' of the flames and helped increase their spread. Basically speaking, it would have acted like a natural fire trap, keeping the flames concentrated and allowing the quicklime and saltpeter to do their work of increasing the temperature
Sulphur, otherwise known as brimstone, is another 'must have' in the list of ingredients. Sulphur is commonly found around volcanic regions, and historically, one such area was smack-dab in the middle of the Byzantine Empire, namely the area known as Cappadocia. Thus, the ingredient was not only easily obtainable, but its properties make it a definite key element. Not only does sulphur act as an oxidizer, this bight yellow soft solid increases when in liquid form and is highly flammable. Can we say BOOM?!
I have already mentioned crude oil (or petroleum), now let me get a bit more specific. I am speaking of naptha. Interesting enough, coal tar can be broken down to produce naptha, and as we have already seen, bitumen (or tar) is an ingredient in our 'mix'. Coincidence? I think not. It can also be extracted from wood, and given that this was a maritime society, well, it makes perfect sense if you ask me. It is highly volatile and insoluble in water. Again, can we say..KABLOOEY?!
Next on our list is tartar. This is an ingredient in the making of potash (or potassium carbonate for the scientifically snooty among us). It acts as a 'lightning rod' or electrolyzer when it comes in contact with water. One can only imagine how this would work in conjunction with the catalysts and bases we have already mentioned. Easily mined from water-soluble salts, it would have been quite easy to obtain. Salts..ocean...get the connection?
Last, but most decidedly not least is the 'glue' to bind it all together..namely resin or pitch. Pitch can be made from either plant based sources (in which case it is called resin) or our old friend petroleum (in which case it is called..tada..bitumen (or pitch..so sue me, I was going for the dramatic flair). One interesting tidbit I ran across in my research was mention of a specific plant called sarcocolla, a small shrub native to Southern Africa, and the sticky substance derived from it. Given the vast spread of the Byzantine Empire and the 'duty' of pitch in the 'recipe', I would hazard to believe that this particular plant may have been harvested a time or two for such a purpose. It should also be noted that some resins contain heptane, which are highly explosive and flammable.
And there you have it, the 'recipe' for Greek Fire. Though we cannot know for certain if it is the original (or even if it would work at all), given the properties of the ingredients I have found, I would be willing to bet a coin or two in its favor.
Benjamin Fraser
There had to be at least one ingredient that would explain why the thing burned so well. I would think oil might be a possibility as it helps to strengthen a fire. Oil would also explain why it was so hard to fight Greek Fire and why it continued to burn even on water. Another possibility is pitch. It would allow the Greek Fire to stick to an object like a wall - acting a bit like glue - and it would also make it much harder to extinguish the fire. Another gluelike substance that burns quite well is resin. That would certainly have been easy to acquire, even back then. As Greek Fire was also stored in bottles and thrown, it makes sense to have some ingredient that makes it stick to wherever it is thrown. To have a bit of an explosion, they might have used sulfur which can be extremely dangerous when mixed with the right substances. It also burns extremely well and is used still today, for example for matches. Another substance that might have been part of the Greek fire is saltpeter. This has been known to be used for all kinds of explosive purposes. During the time period in which Greek fire was mainly used, all of those ingredients would have been available (at least to someone with enough knowledge to know what to look for).
Kiriuta Yuzuki
From the little research I'd done, Greek Fire seemed to be an extremely effective fire weapon used by the Greeks. It even burns over water! (never thought ASoIAF's wildfire had a basis -- nay, source, in reality) With that in mind, I can see why it's a closely guarded secret that's kept to the grave. It was said that modern chemistry is still unable to replicate Greek Fire. It says something about how mysterious and complex the ritual seemed to be.
It was very interesting, going down the rabbit hole of research! For instance, most resources appeared to only give the (approximate) ingredients and the (approximate) method of making one. it makes sense that given the secrecy..but it's even more interesting that only the ingredients had been known, because in alchemy and chemistry the ratio and the exact method/ritual held equal, if not more importance than the ingredients. Why was it that only the ingredients had been known? Is it first hand account? Or was it something else; like a shopping log? Or an attempt of espionage?
Trying to decode the context is a fun exercise.
That aside, As far as ingredients go, most resources seemed to a different set of ingredients.
Wikipedia claimed : pine resin, naphtha, quicklime, sulfur, or niter
Another site claimed : resin, quicklime, saltpeter, bitumen, sulfur, pitch.
Another wrote: "Greek Fire is made as follows: take sulfur, tartar, sarcocolla, pitch, melted saltpeter, petroleum oil, and oil of gum, boil all these together, impregnate tow [i.e., the coarse or broken part of flax orhemp, prepared for spinning] with the mixture, and the material is ready to be set on fire. "
"This fire cannot be extinguished by urine, or by vinegar, or by sand ... Flying fire may be obtained in the following manner: take one part of colophony [rosin], the same of sulfur, and two parts of saltpeter. Dissolve the pulverized mixture in linseed oil, or better in oil oflamium. Finally, the mixture is placed in a reed or a piece of wood which has been hollowed out.When it is set on fire, it will fly in whatever direction one wishes, there to set everything on fire."
What are they?
How are they used to make fire?
And most importantly, how are they part of the Greek Fire?
Wikipedia made a claim that Greek Fire must be prepared and used in a specific way for it to function effectively, from the treatment to the ships to the siphons used. I would tend to agree with that. Regardless of alchemy, it would make much sense for a weapon of this caliber and complexity to have an equally specific method for using it.
Trying to dissect the function, a substance must be used to either block water, to prevent the fire from being extinguished, or to even spread the fire via water. I don't know much about chemistry, but I think the last one can be achieved.
Another element would catch fire when exposed to air. From description they didn't seem to require any outside form of fire for it to start. That would mean the substance is highly flammable with perhaps a trait to catch fire easier when exposed to the air.
Another element would function to spread the fire. They would also need to be able to float above the water so as to keep the fire burning.
Another element may function as the 'liquid' part of the Greek fire. Meaning they bind the elements together, and they kept it in a form of liquid as opposed to, say, powder. They may also function as a 'lock' for the elements; to avoid the elements from igniting before it should a.k.a before it was exposed
Now back to the list of ingredients.... A lot of them are substances that are admittedly unknown for me. I know sulfur, and saltpeter, and oils, and resin, but others...I have no idea. Luckily some seems to offer explanation about what each substance were doing. For instance :
It made sense that there are saltpeter inside; it would make Greek Fire essentially a form of explosives. Equally so with sulfur.
Quicklime interestingly appeared to have an explosive reaction with water. Wikipedia essentially said that the reaction between quicklime and water does not achieve the same result as Greek Fire. But if -- and this is a big if-- they are capable of mixing quicklime with other, more flammable material; I can see quicklime being the catalyst for the explosions.
Bitumen sounds highly flammable. I can see how it's used to help the substance catch MORE fire.
From the above list of resources, various oils are posited to be a potential ingredient from petroleum to linseed oils...Given oil's traits of not mixing with water, I can see people using oils of various kinds to help spread the Greek Fire. And best of all, they are highly flammable.
I can also see resin being used for the same purposes. If they were being made thick enough to prevent dissolving in water, I can see them used to bind the substances together and avoid being mixed with water.
And pitch; if that is what it did, they sound like the perfect thing to use to prevent the mixing of Greek Fire and water.
Assuming the list of ingredients are true, from my limited understanding making a liquid, flammable substance that can be ignited on water is not impossible. Resin and pitch and oil are used to bind the explosives and which are saltpeter and sulfur. Quicklime is used as the catalyst, the part that's the easiest to explode when touching water. On the other hand resin, oil, and bitumen are also used to spread the fire around. Pitch, oils, and if possible, resin, are used to keep the liquid floating above water, essentially to keep the fire burning above water.
.....And to achieve that, is another matter entirely. Which I guess goes back to the point of alchemy..
It was very interesting, going down the rabbit hole of research! For instance, most resources appeared to only give the (approximate) ingredients and the (approximate) method of making one. it makes sense that given the secrecy..but it's even more interesting that only the ingredients had been known, because in alchemy and chemistry the ratio and the exact method/ritual held equal, if not more importance than the ingredients. Why was it that only the ingredients had been known? Is it first hand account? Or was it something else; like a shopping log? Or an attempt of espionage?
Trying to decode the context is a fun exercise.
That aside, As far as ingredients go, most resources seemed to a different set of ingredients.
Wikipedia claimed : pine resin, naphtha, quicklime, sulfur, or niter
Another site claimed : resin, quicklime, saltpeter, bitumen, sulfur, pitch.
Another wrote: "Greek Fire is made as follows: take sulfur, tartar, sarcocolla, pitch, melted saltpeter, petroleum oil, and oil of gum, boil all these together, impregnate tow [i.e., the coarse or broken part of flax orhemp, prepared for spinning] with the mixture, and the material is ready to be set on fire. "
"This fire cannot be extinguished by urine, or by vinegar, or by sand ... Flying fire may be obtained in the following manner: take one part of colophony [rosin], the same of sulfur, and two parts of saltpeter. Dissolve the pulverized mixture in linseed oil, or better in oil oflamium. Finally, the mixture is placed in a reed or a piece of wood which has been hollowed out.When it is set on fire, it will fly in whatever direction one wishes, there to set everything on fire."
What are they?
How are they used to make fire?
And most importantly, how are they part of the Greek Fire?
Wikipedia made a claim that Greek Fire must be prepared and used in a specific way for it to function effectively, from the treatment to the ships to the siphons used. I would tend to agree with that. Regardless of alchemy, it would make much sense for a weapon of this caliber and complexity to have an equally specific method for using it.
Trying to dissect the function, a substance must be used to either block water, to prevent the fire from being extinguished, or to even spread the fire via water. I don't know much about chemistry, but I think the last one can be achieved.
Another element would catch fire when exposed to air. From description they didn't seem to require any outside form of fire for it to start. That would mean the substance is highly flammable with perhaps a trait to catch fire easier when exposed to the air.
Another element would function to spread the fire. They would also need to be able to float above the water so as to keep the fire burning.
Another element may function as the 'liquid' part of the Greek fire. Meaning they bind the elements together, and they kept it in a form of liquid as opposed to, say, powder. They may also function as a 'lock' for the elements; to avoid the elements from igniting before it should a.k.a before it was exposed
Now back to the list of ingredients.... A lot of them are substances that are admittedly unknown for me. I know sulfur, and saltpeter, and oils, and resin, but others...I have no idea. Luckily some seems to offer explanation about what each substance were doing. For instance :
- Quicklime - Quicklime also known as calcium oxide (white, caustic, lumpy powder )
- Saltpeter - Saltpeter aka Sodium nitrate is a type of salt which has long been used as an ingredient in explosives
- Bitumen - Asphalt and tar are the most common forms of bitumen. The city of Carthage was easily burnt down due to extensive use of bitumen in construction.
- Sulpher (Sulfur) - Sulfur is a soft bright yellow solid. Unlike most other liquids, increases with temperature due to the formation of polymer chains. Because of its flammable nature, sulfur also finds use in matches, gunpowder, and fireworks.
- Resin - Resin is a sticky liquid produced by most plants. Some reins contain heptane which is explosively flammable
- Pitch - Pitch is a thick, dark, sticky substances obtained from the distillation residue of coal tar, wood tar, or petroleum and used for waterproofing
It made sense that there are saltpeter inside; it would make Greek Fire essentially a form of explosives. Equally so with sulfur.
Quicklime interestingly appeared to have an explosive reaction with water. Wikipedia essentially said that the reaction between quicklime and water does not achieve the same result as Greek Fire. But if -- and this is a big if-- they are capable of mixing quicklime with other, more flammable material; I can see quicklime being the catalyst for the explosions.
Bitumen sounds highly flammable. I can see how it's used to help the substance catch MORE fire.
From the above list of resources, various oils are posited to be a potential ingredient from petroleum to linseed oils...Given oil's traits of not mixing with water, I can see people using oils of various kinds to help spread the Greek Fire. And best of all, they are highly flammable.
I can also see resin being used for the same purposes. If they were being made thick enough to prevent dissolving in water, I can see them used to bind the substances together and avoid being mixed with water.
And pitch; if that is what it did, they sound like the perfect thing to use to prevent the mixing of Greek Fire and water.
Assuming the list of ingredients are true, from my limited understanding making a liquid, flammable substance that can be ignited on water is not impossible. Resin and pitch and oil are used to bind the explosives and which are saltpeter and sulfur. Quicklime is used as the catalyst, the part that's the easiest to explode when touching water. On the other hand resin, oil, and bitumen are also used to spread the fire around. Pitch, oils, and if possible, resin, are used to keep the liquid floating above water, essentially to keep the fire burning above water.
.....And to achieve that, is another matter entirely. Which I guess goes back to the point of alchemy..
Niamh Cassidy
For its day, Greek Fire was an extremely powerful weapon, able to burn ferociously and resistant to being put out with water. In fact, it could burn very well on the water and was often used in naval battles. But because it was so potent, those who knew how to make it generally carried the secret of it to their graves, afraid that their enemies would be able to use it against them.
Mopst theories as to the recipe for Greek Fire involve ingredients such as quicklime, saltpeter, bitumen, sulfur, naphtha, resin, and pitch. Pitch and resin are both very sticky substances and would have helped the Greek Fire to stick to its target, which is another reason why it was so effective. Also, some types of resin are naturally flammable. Bitumen is closely related to pitch -- both were used for waterproofing in ancient times and both are highly flammable. When Carthage burned, it supposedly burned very quickly due to the high amount of bitumen in its walls.
A form of naphtha was also used to create napalm, the modern equivalent of Greek Fire, and if naphtha was in the ancient recipe, then it would have helped make the Greek Fire thick and difficult to douse. Quicklime, or calcium oxide, reacts very quickly with water, and this chemical process generates large amounts of heat, making it an obvious candidate for an ingredient in Greek Fire. Sulfur is used in gunpowder, while saltpeter is found in explosives.
While often used on ships, with the Greek Fire being poured out onto the waters and lit on fire as it fell to the surface, it could also be used as an early form of hand grenade. Pottery vessels would be filled with the Greek Fire and thrown into the midst of the enemy. The troops who handled the substance wore specially fireproofed armor and received special training in how to use it -- but I don't think I would ever have wanted to use it myself!
http://neobyzantium.com/greek-fire-the-byzantine-secret-weapon/
http://www.middle-ages.org.uk/greek-fire.htm
http://www.peterschemical.com/calcium-oxide/
Mopst theories as to the recipe for Greek Fire involve ingredients such as quicklime, saltpeter, bitumen, sulfur, naphtha, resin, and pitch. Pitch and resin are both very sticky substances and would have helped the Greek Fire to stick to its target, which is another reason why it was so effective. Also, some types of resin are naturally flammable. Bitumen is closely related to pitch -- both were used for waterproofing in ancient times and both are highly flammable. When Carthage burned, it supposedly burned very quickly due to the high amount of bitumen in its walls.
A form of naphtha was also used to create napalm, the modern equivalent of Greek Fire, and if naphtha was in the ancient recipe, then it would have helped make the Greek Fire thick and difficult to douse. Quicklime, or calcium oxide, reacts very quickly with water, and this chemical process generates large amounts of heat, making it an obvious candidate for an ingredient in Greek Fire. Sulfur is used in gunpowder, while saltpeter is found in explosives.
While often used on ships, with the Greek Fire being poured out onto the waters and lit on fire as it fell to the surface, it could also be used as an early form of hand grenade. Pottery vessels would be filled with the Greek Fire and thrown into the midst of the enemy. The troops who handled the substance wore specially fireproofed armor and received special training in how to use it -- but I don't think I would ever have wanted to use it myself!
http://neobyzantium.com/greek-fire-the-byzantine-secret-weapon/
http://www.middle-ages.org.uk/greek-fire.htm
http://www.peterschemical.com/calcium-oxide/
