- Ernst Badian
- and T. W. Potter
- Science, Technology, and Medicine
Canals (fossae, διώρυγες). Drainage and irrigation canals were widely used in antiquity. The oldest, in Iraq, date to the sixth millennium bce, while in Egypt they were in use from the fourth millennium. Thenceforth, in both Mesopotamia and Egypt, irrigation canals came increasingly to be employed, although long-distance straight-line waterways are mainly a development of the first millennium bce; Sennacherib's celebrated Jerwan aqueduct (691 bce), ran for over 80 km. (50 mi.) from the uplands to Nineveh (1). But in Mesopotamia full state-controlled irrigation systems appeared only on Sasanian times (226–640 ce). In Greece, Lake Copais was first reclaimed by the Mycenaeans (Strabo 9. 2. 40); Hellenistic works (by Crates of Chalcis: Strabo 9. 2. 18) and Hadrianic dykes are also attested; Xerxes' canal through Mt. Athos was for military ends. Projects (never realized) to pierce the Isthmus of Corinth are intermittently attested from Periander's time (see diolkos). In Sicily, Empedocles of Acragas drained low-lying terrain around Selinus in 444 bce (Diog. Laert. 8. 59–60), and the port-city of Spina, founded c.540 bce in NE Italy, had a ‘grand canal’, and a grid of other canals to create rectangular blocks, in which were buildings on wooden piles. The canals may have been constructed by the Etruscans, whose skills in this area of engineering were noted (e.g. Pliny (1), HN 3. 20); there are still conspicuous traces in southern Etruria (and also Latium) of underground cuniculi—tunnels, for land reclamation. The level of the Albanus lacus was also lowered by means of a cuniculus, 1,800 m. (1,968 yds.) in length, and a 24-km. (15-mi.-) long canal, built in the 4th cent. bce (Livy 5. 15. 12).
The Romans used canals extensively, learning much from the Etruscans who, in the 6th cent. bce, did much to alleviate flooding problems in Rome itself (Livy 1. 38. 2). A canal was cut by M. Cethegus (consul 160 bce) through the Pomptine Marshes which, although not particularly successful as a drainage measure, nevertheless proved successful as an alternative mode of travel to the via Appia (Hor. Sat. 5. 5.). In the Po valley (see padus), where land reclamation was, according to tradition, begun by the Etruscans (Plin. HN 3. 115), M. Aemilius Scaurus (1) built the first Roman canals in 109 bce (Strabo 5. 1. 11); they were intended to be both navigable and for drainage, and led to a highly successful development of the region. Under Augustus, a canal was dug between Ravenna and the Po estuary, creating an important harbour (Plin. HN 3. 119) and there were significant attempts to canalize the mouth of the Tiber. Claudius used 30,000 men for eleven years in an attempt to drain the Fucinus Lacus (Suet. Claud. 20. 1–2; 21. 6).
There were significant works of canalization in many provinces (e.g. by C. Marius (1) at the mouth of the Rhône; by Drusus, and later Cn. Domitius Corbulo, at the mouth of the Rhine; and the Car Dyke of the western Fens of Britain, probably a Hadrianic catch-water system). But Egypt remained the principal country of canals. Alexandria (1) was connected with the Nile by the ‘Canopus Canal’; and though earlier Egyptian schemes for digging through the isthmus of Suez apparently failed, Ptolemy (1) II, using some of their workings, built a canal from the Nile (near Heliopolis) to the Bitter Lakes, which he connected with Arsinoë (2). Improved under Trajan and Hadrian, it enabled Alexandria to become the principal centre for seaborne trade between the east and the Mediterranean.
- R. J. Forbes, Irrigation and Drainage (1955).
- R. M. Adams, Land behind Baghdad (1965).
- T. W. Downing and M. Gibson (eds.), Irrigation's Impact upon Society (1974).
- T. W. Potter in T. Rowley (ed.), The Evolution of Marshland Landscapes (1981), 1 ff.
- B. Isserlin and others, Annual of the British School at Athens 1994, 277–84 (Athos canal).
- R. Hope-Simpson and D. Hagel, Mycenaean Fortifications, Highways, Dams and Canals (2006).