Byzantine Weapons and Warfare

[Eleatic Guest]

I seem to recall a manuscript showing a Galley using it's Greek fire against a foe....a continuous stream is depicted ( which was presumably of a few seconds duration), like modern flamethrowers......

I have no idea about modern flamethrowers...cant they boast a continuous flame until being empty? I was asking because I stumbled over this claim:

Flamethrower, double piston: Although the single piston flamethrower was first developed in the Byzantine Empire during the 7th century, the 10th century Chinese flamethrower, or Pen Huo Qi, boasted a continuous stream of flame by employing double piston syringes (which had been known since the Han Dynasty) spouting Greek fire which had been imported from China's maritime trade contacts in the Middle East

The author makes it look like the Byzantine "single piston" version was not capable of a continuous flame. True or not?