Meridian von Giovanni Domenico Cassini - Bologna - RN - Italy - Great Lines of Earth on Waymarking.com

Cassini's Meridian Line
La meridiana

The church hosts also a marking in the form of a meridian line inlaid in the paving of the left aisle in 1655; it was calculated and designed by the astronomer Giovanni Domenico Cassini, who was teaching astronomy at the University. A meridian line does not indicate the time, but instead the day of the year, as well as determining the length of the solar year. At 66.8 metres (219 ft) it is one of the largest astronomical instruments in the world, allowing measurements that were for the time uniquely precise; Cassini and Domenico Guglielmini published an illustrated account of how the meridian was accomplished in 1695.
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The sign reads:
meridiane huius liniae tota longitudo intra verticalem et centralem solis radium in hyberno solstitio est sexcentimillesima pars circuitus uniuersae terrae

translated:
and the whole of the length of the vertical articulation within the centrality of the liniae meridiane of this summer 's solstice of winter the sun's ray of light on a part of the circuits of the whole body of the earth is sexcentimillesima

Line type: Historical meridian Tolerance: 0 If other type, please explain.: Not listed

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Date Logged Log User Rating   10/17/2018 CADS11 visited it