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Dioptra

A dioptra (sometimes also named dioptre or diopter, from Greek: διόπτρα) is a classical astronomical and surveying instrument, dating from the 3rd century BC. The dioptra was a sighting tube or, alternatively, a rod with a sight at both ends, attached to a stand. If fitted with protractors, it could be used to measure angles.

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Dioptra

Nodes22
Edges21
Triples89
Avg. degree1.91
Density0.090909
Components1

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Dioptra

Top relations

related to External links · 34
Dioptra → Alexandria, An Astronomical Determination, Analemma Methods, Antiquity, Apostol, Biography, Brill’s New Pauly, Centaurus, Christine, Classical Tradition, Distance, Eckart, Engineering, English Edition, Francis, Gascoigne, Gentry, Helmuth Schneider, Heron, Heron's Dioptra
related to Further reading · 21
Dioptra → Ancient Astronomy, BC, Be Reborn, Berlin, Cambridge University Press, Evans, Greece, How Science Was Born, Isaac Moreno Gallo, ISBN, Michael Jonathan Taunton Lewis, Oxford University Press, Practice, Rome, Russo, Springer, Surveying Instruments, The Dioptra Tesis, The Forgotten Revolution, The History
has application · 7
Dioptra → Beyond, Eupalinian, For, Greece, It, Rome, The
related to history · 7
Dioptra → Alexandria's, Greek, Hellenistic, Hero, Notably, Over, The
related to Use · 5
Dioptra → Adapted, Euclid, Geminus, Greek, It
related to Advantages and disadvantages · 4
Dioptra → Additionally, However, Its, The
related to Comparison with other instruments · 3
Dioptra → It, The, While
related to How it works · 3
Dioptra → In, The, When

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Important terminology

surveying theodolite instrument used use measure angles engineering instruments also greek groma alidade accuracy astronomical century sighting rod ancient made

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
wind or temperature changesinstance ofThe sighting tube or rod could be affected by environmental factors0.80text
which could introduce errorsinstance ofThe sighting tube or rod could be affected by environmental factors0.80text
the gromainstance ofComparison with other instrumentsThe dioptra's design and functionality can be compared to other contemporary instruments0.80text
the alidadeinstance ofComparison with other instrumentsThe dioptra's design and functionality can be compared to other contemporary instruments0.80text
and the later theodoliteinstance ofComparison with other instrumentsThe dioptra's design and functionality can be compared to other contemporary instruments0.80text
Dioptrahas applicationBeyond0.60section
Dioptrahas applicationGreece0.60section
Dioptrahas applicationRome0.60section
Dioptrahas applicationIt0.60section
Dioptrahas applicationThe0.60section
Dioptrahas applicationFor0.60section
Dioptrahas applicationEupalinian0.60section

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