The greeks that were around before had developed one, but not as terrifying as this. Around 919 A.D, the ancient Chinese developed a horrifying weapon that made soldiers fear for their lives. The chinese had built an ancient flamethrower, unique from the others. This new weapon could spray a continuous stream of flame into the opposing army. More often than not, the flamethrowers would be loaded onto ship decks to shoot at the enemy ships. The stream of flames would encircle the enemy armada in a fiery wreath, sending the ship and it's crew to watery graves.
In the Machine
The ancient chinese flamethrower was a piston powered mechanism, using a chemical similar to gasoline to spray the hot flame. It would spray "fiery hot oil" at the enemy, said Lin Yu. This is the first credible referance to the ancient weapon. The piston-bellows in the machine would pump flammable liquid up a tube, where a spark would ignite it just before sending the flame towards the enemy. For more info, go here
Physics Behind Flame
Basic physics apply, where the Potential Chemical of the gasoline gets ignited because of the heat and light energy given off of the spark. When these two combine, it is a fiery stream of death flying towards you!
From their creation in Ancient Greece, flamethrowers have been used by hundreds of nations for wartime weapons.
During WWII, flamethrowers were vital in Pacific Island assaults, used for burning forests or bunkers.
In WWII, flamethrowers could be mounted or built into tanks for an armored flame assault.
Experiments with flammable material finally led to the creation of the chemical Napalm in the early 1900's.
Ships succumbed to the flamethrowers might for centuries... until metal ships began to hit the waters of the world.