Hand-held projectors thumb|Detail of a cheirosiphōn The portable cheirosiphōn ("hand-siphōn"), the earliest analogue to a modern flamethrower, is extensively attested in the military documents of the 10th century, and recommended for use in both sea and land. They first appear in the Tactica of emperor Leo VI the Wise, who claims to have invented them. Subsequent authors continued to refer to the cheirosiphōnes, especially for use against siege towers; Nikephoros II Phokas also advises their use in field armies, with the aim of disrupting the enemy formation. Although both Leo VI and Nikephoros Phokas claim that the substance used in the cheirosiphōnes was the same as in the static devices used on ships, Haldon and Byrne consider that the former were manifestly different from their larger cousins, and theorize that the device was fundamentally different, "a simple syringe [that] squirted both liquid fire (presumably unignited) and noxious juices to repel enemy troops." The illustrations of Hero's Poliorcetica show the cheirosiphōn also throwing the ignited substance.
Hand-held projectors thumb|Detail of a cheirosiphōn The portable cheirosiphōn ("hand-siphōn"), the earliest analogue to a modern flamethrower, is extensively attested in the military documents of the 10th century, and recommended for use in both sea and land. They first appear in the Tactica of emperor Leo VI the Wise, who claims to have invented them. Subsequent authors continued to refer to the cheirosiphōnes, especially for use against siege towers; Nikephoros II Phokas also advises their use in field armies, with the aim of disrupting the enemy formation. Although both Leo VI and Nikephoros Phokas claim that the substance used in the cheirosiphōnes was the same as in the static devices used on ships, Haldon and Byrne consider that the former were manifestly different from their larger cousins, and theorize that the device was fundamentally different, "a simple syringe [that] squirted both liquid fire (presumably unignited) and noxious juices to repel enemy troops" The illustrations of Hero's Poliorcetica show the cheirosiphōn also throwing the ignited substance.