Mathematical description of the rhumb line
Descripción matemática de la loxodrómica
- Date
- 1537 · confidence high
- Place
- Lisbon, Portugal
- Credited to
- Pedro Nunes
- Field
- Movement
What was discovered
Portuguese royal cosmographer Pedro Nunes showed that a ship sailing a constant compass bearing does not follow a great circle but a spiral that approaches, without ever reaching, the pole: the rhumb line. His analysis laid the mathematical groundwork that Mercator would later use to design his map projection.
What it led to
- Mercator projection (1569)
- Dead-reckoning navigation on a constant bearing
Built on
- Mariner's compass
- Portolan charts