Greek and Roman portable sundials. An ancient essay in approximation
type: Item
instance of: scholarly article
title: Greek and Roman portable sundials. An ancient essay in approximation
zbMATH Open document ID: 0968.01008
author: M. T. Wright
published in: Archive for History of Exact Sciences
publication date: 2001-09-12T00:00:00Z
review text: The author reports about nine portable sundials that have survived from Antiquity. These devices show the usual subdivision of the time from sunrise to sunset into twelve equal hours. (In contrast to the modern 24 equal hours from midnight to midnight.) Fixed sundials work exactly in principle, but the portable ones show the time only approximately. The author explains their working in detail and calculates their error according to the time of the day, the season of the year, and the observers latitude. Exact values are obtained at the equinoxes, but otherwise the deviation from the exact time may be as much as 15 minutes (in the locations of the antique world). This can be neglected if only the approximate hour of the day is of interest.
reviewed by: Benno Artmann
Mathematics Subject Classification ID: 01A20
zbMATH DE Number: 1556787
zbMATH Keywords: sundials
describes a project that uses: SUNDIALS
MaRDI profile type: Publication
full work available at URL: s004070000024
OpenAlex ID: W1971579747
DOI: 10.1007/S004070000024
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description: scientific article; zbMATH DE number 1556787