Old Concepts, New Applications: Water, Fire, and Relevant Technologies Producing Dual-Use Items in Byzantium and the Neighbouring Areas

This paper examines the ‘dual-use items’ (a term which encompasses goods and technologies that have both civilian and military applications) and their production in a historical perspective, focusing on Byzantium and neighbouring areas. Using as a starting point the ‘dual use’ concept of fire and water producing energy goods as well as their technological applications, it studies their evolution in Byzantium and her neighbours. Relevant lexical references attest the concept of fire as energy producer, (e.g. fire as δραστικὸν στοιχεῖον-active element and its use for thermal energy through the δραστήριος κίνησις-active movement of pyroxenes or for light/fire production through τῷ δραστικῷ τῆς θρυαλλίδος -the active action of the fuse) both in everyday life and in war. Similarly, water was seen both as an active energy producer by use of hydropower and as a weapon in wartime, as attested by submerging enemies (ἐξυδατώνειν) through river hydraulics. Relevant processing techniques developed out of various fields (tanning, metallurgy, glass and gold working, pharmacy/medicine, ceramics), and chemical operations as using the ἄμβιξ/alembic, produced both luxury/everyday products and oils and incendiary substances which could be thrown against enemies in stone/ceramic/glass grenades. Cross-references to Greek authors in Arab treatises, or to Arabs ‘περιβοήτου[ς] έν τεχνουργίᾳ’ mentioned in Greek manuscripts, attested to the existence of dual-use items as well as to the interaction between medieval Byzantium and the Islamic world. The question remains as to the development of such knowledge being due to direct exchange through observation and ‘industrial’ spying, or to a parallel approach with innovations inspired indirectly from perusal of ancient authors and experimentation. Military manuals seem to privilege the direct approach but silence or ciphers in written treatises when referring to the production of inflammable substances (as the alcohols), point rather to the second approach or to a combination of both.