Polymeter
From Inventions
Name coined by the inventor (in Latin polimetrum), by combining the Greek poly (many) and metron (measurement).
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Inventor
Martin Waldseemüller
Historic Period
1512
Description
Instrument for astronomical and terrestrial measurements and for compiling topographic and corographic maps. Invented by the Viennese cosmographer Martin Waldseemüller, the instrument is the prototype of the modern theodolite. A square panel bears a goniometric circle divided into 360° (four 90° sectors) with the shadow square engraved on it. At the centre rotates the diopter, carrying a vertical rod at the top of which pivots a half-disc – similar to the lower part of the back of an astrolabe or a double quadrant – bearing a degree scale, shadow square and sights on the upper straight side. The diopter on the horizontal circle measures the position angles (azimuth) while the sights on the vertical half-disc measure the zenith angles, allowing the distances of places to be calculated from a single station.
Bibliographical Resources
Reisch, Gregor. Margarita philosophica nova cui insunt sequentia epigrammata in commentationem operis, institutio grammaticae latinae praecepta logices rhetoricae informatio ars memorandi ravennatis beroaldi modus compendi epi arithmetica musica plana geometrie principia astronomia cum quibusdam de astrologia philosophia naturalis moralis philosophia cum figuris. Stassburg, Grüninger, 1512.
Reisch, Gregor. Margarita filosofica del R.P.F. Gregorio Reisch: nella quale si trattano tutte le dottrine comprese nella ciclopedia. Accresciuta di molte belle dottrine da Oratio Fineo matematico regio, di novo tradotta in italiano da Gio. Paolo Gallucci. In Vinegia, presso Barezzo Barezzi, 1599, VII.
Gallucci, Giovanni Paolo, Della fabbrica et uso di diversi strumenti di astronomia e cosmografia, Venezia, Roberto Maietti, 1598, VII.
Taylor, Eva Germaine Rimington. La cartografia, il rilevamento e la navigazione, in Storia della tecnologia.A cura di Charles Singer.Torino, P. Boringhieri, 1984, vol. 7, pp. 548-549.
Images
Author of the entry: Filippo Camerota