Portolan Chart

ポルトラーノ海図 / 13th–17th century / Style / Diagrammatic Expression

A medieval working sea chart, crossed by radiating rhumb lines. Coastlines and place names run precisely along the vellum while flags and monsters fill the empty water, from a time when a map's usefulness and its ornament had not yet parted.

Portolan Chart — Portolan chart of the Mediterranean, 16th century — Wikimedia Commons / Public domain — Portolan chart of the Mediterranean, 16th century — Wikimedia Commons / Public domain

Portolan Chart — Portolan chart of the Aegean Sea — Wikimedia Commons / Public domain — Portolan chart of the Aegean Sea — Wikimedia Commons / Public domain

Portolan Chart — Catalan Atlas, Europe section 1375 — Wikimedia Commons / Public domain — Catalan Atlas, Europe section 1375 — Wikimedia Commons / Public domain

At a glance

Visual cues

Radiating rhumb lines
Names perpendicular to coasts
The vellum ground
Flags and monsters as ornament

Best used for

Books and exhibitions telling the story of routes or trade as a map
Ornamental maps whose real subject is the memory held in place names

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Dictionary entry

Type: Names packed perpendicular to the coast, key ports raised in red
Composition: Several compass roses with straight lines radiating across the sheet
Material: Black and red on a vellum ground, flags and monsters in open water
Caution: Drawing rhumb lines as pattern while ignoring how they answer the roses gives ornament that no longer looks like an instrument of navigation.
Further study: the Catalan Atlas lineage / the structure of rhumb lines / charts as state secrets

Related entries

Celestial Atlas (星図の様式)Same Diagrammatic Expression lineage.Compare Portolan Chart and Celestial Atlas
Hatsusaburō Panoramic Map (初三郎式鳥瞰図)Same Diagrammatic Expression lineage.Compare Portolan Chart and Hatsusaburō Panoramic Map

Cite this entry

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Link: https://indexstyle.org/styles/portolan-chart
Markdown: [Portolan Chart — IndexStyle](https://indexstyle.org/styles/portolan-chart)
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