In the ancient Greek and Roman worlds, centred as they were on the Mediterranean, maritime transport was far more practical than land transport for long- and even medium-distance trade. Most ships seem to have been of medium size (around 70 tonnes burden) and to have been owned and run by a shipper who both carried goods as freight and traded on his own account. There were also many individual merchants who hired shipping as needed for their ventures. Then as now, the major expense in trading was the investment in purchasing goods; roughly, one cargo of wheat was worth as much as the ship. Hence a merchant, whether or not also a shipowner, often needed third-party finance, for which, because of the peculiar risks involved, a special type of loan was used. This was the maritime loan—nautikon daneion in Greek, nauticum faenus or mutua pecunia nautica in Latin.The maritime loan is first attested in 4th-century bce Athens, in four speeches attributed to Demosthenes, of which the most informative is the prosecution of the brother of a pair of merchants for fraudulent default on a loan (Dem.