Periplus


A periplus or periplous is a manuscript document that lists the ports and coastal landmarks, in order and with approximate intervening distances, that the captain of a vessel could expect to find along a shore. In that sense the periplus was a type of log. It served the same purpose as the later Roman itinerarium of road stops; however, the Greek navigators added various notes, which if they were professional geographers became part of their own additions to Greek geography.
The form of the periplus is at least as old as the earliest Greek historian, the Ionian Hecataeus of Miletus. The works of Herodotus and Thucydides contain passages that appear to have been based on peripli.

Etymology

Periplus is the Latinization of the Greek word περίπλους, is "a sailing-around." Both segments, peri- and -plous, were independently productive: the ancient Greek speaker understood the word in its literal sense; however, it developed a few specialized meanings, one of which became a standard term in the ancient navigation of Phoenicians, Greeks, and Romans.

Known ''peripli''

Several examples of peripli that are known to scholars:

Carthaginian

n sailors had long had their own sailing guide books, called Rahnāmag in Middle Persian.
They listed the ports and coastal landmarks and distances along the shores.
The lost but much-cited sailing directions go back at least to the 12th century. Some described the Indian Ocean as "a hard sea to get out of" and warned of the "circumambient sea," with all return impossible.

Tactic of naval combat

A periplus was also an ancient naval maneuver in which attacking triremes would outflank or encircle the defenders to attack them in the rear.