Theodolite
Teodolito
- Date
- 1571 · confidence high
- Place
- London, England
- Credited to
- Leonard Digges (Pantometria, published by Thomas Digges, 1571); Gemma Frisius (triangulation, 1533)
- People
- 👤 Leonard Digges1515–1559👤 Regnier Gemma Frisius1508–1555
- Field
- Knowledge & symbols
What it is
An instrument with graduated horizontal and vertical circles and an alidade for measuring angles in surveying, combined with Frisius's method of triangulation. The foundation of geodetic cartography.
Similar instruments (Waldseemüller's polimetrum, 1512) predate the name.
What it led to
- The triangulation of France by the Cassini family and the first national topographic map
- The surveying of enclosures, canals and mines
- The measurement of the meridian arc and the shape of the Earth
Built on
- Early planispheric astrolabec. 150 CE
- Vernier scale1631 (nonio de Nunes, 1542)
- Geometric quadrant
- Magnetic compass
Made possible
- Snellius's triangulation (Eratosthenes Batavus)1615-1617
- Picard's arc measurement (La mesure de la Terre)1669-1670
- Struve Geodetic Arc1816-1855
- Theodolite with telescopic sight (Sisson, 1720s)
- Ramsden's great theodolite (1787)
- Engineer's level