The Emperor Leo VI. speaks of the “artificial fire discharged by means of siphons;”[95] the Emperor Constantine VII. speaks similarly of “the wet-fire projected by means of siphons;”[96] and if we translate _siphon_ by _tube_ both phrases are intelligible, but neither gives any hint as to the means by which the mixture was expelled from the tubes. But like so many other military words, _siphon_ has (at least) two meanings, and signifies not only a tube, but a _fire-engine_, or _water-engine_, or _squirt_. Heron of Alexandria (_cir._ 130 B.C.) begins his description of a fire-engine with the words: “The _siphons_ used for the extinction of fire are made as follows.”[97] Pliny the Younger (_cir._ 100 A.D.), in a letter to the Emperor Trajan about a fire which had taken place in the town of Nicomedia, observes that “there was not a _sipho_, nor even a bucket, at hand to quench it.”[98] Hesychius in his Greek Lexicon, about the end of the fourth century, gives under σίφων: “an apparatus for pumping water in conflagrations.”[99] If we translate _siphon_ by _water-engine_, as we are perfectly justified in doing, we find that the phrases used by the two Emperors are not only intelligible, but indicate both the mode of projection and the mode of ignition of the sea-fire. The lump of quicklime-naphtha-sulphur was projected, and at the same time ignited, by applying the hose of a water-engine to the breech of the tube, which thus became an integral part of the apparatus to which it gave its name.