Page:History of merchant shipping and ancient commerce (Volume 1).djvu/238

 was then, as it is now, legal evidence, producible in courts of justice in cases of dispute. It contained in its debit and credit divisions the full account of each transaction. When the adversaria, containing the temporary memorandum of the transactions, on which necessary alterations were made before the particulars were transferred to the ledger at the end of each month, if not more frequently, was full, it was thrown aside or destroyed, the ledger being the only record preserved of the transactions which had been completed.

Although the Romans were slow in becoming a great naval power, it is clear that very soon after the battle of Actium they became as powerful at sea as on land; all the leading seafaring states having by this time become subject to the engrossing power of the empire, and there being no longer any naval power to contest with them the supremacy of the Mediterranean Sea: hence, for many years, there was no employment for their fleets, except to protect their commerce and to keep open the communication with the distant colonies of the empire. But long after Rome had swept the sea of her greater opponents, marauders of different races continued to prey upon commerce, so that her merchant traders, engaged on distant voyages, invariably took on board a number of Roman archers to guard their ships from pirates. These men were engaged either to protect the ship when an emergency arose, or to man the oars, and, like the marines of our own time, acted