St. John's College in Annapolis in Anne Arundel County, Maryland — The American Northeast (Mid-Atlantic)
Ptolemy Stone
"Mathematics, by contemplating the uniformity, order, symmetry and calm of divine things, makes its followers lovers of this divine beauty."Ptolemy (c. 100 CE - c. 170 CE)
One of the earliest astronomical devices, the Ptolemy Stone measures elevation of the sun at noon.
By this means, the latitude of the device and the irregularity of the sun's motion may be calculated.
Erected by St. John's Colege.
Topics. This historical marker is listed in these topic lists: Air & Space • Science & Medicine. A significant historical year for this entry is 100 CE.
Location. 38° 58.928′ N, 76° 29.549′ W. Marker is in Annapolis, Maryland, in Anne Arundel County. It is in St. John's College. Marker is on College Avenue (Maryland Route 450) south of King George Street (Maryland Route 450), on the right when traveling south. Touch for map. Marker is at or near this postal address: 60 College Ave, Annapolis MD 21401, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within walking distance of this marker. Max and Elke Schiff (a few steps from this marker); Edmund Berkeley Iglehart (about 300 feet away, measured in a direct line); St. John's College (about 300 feet away); Alexander Magruder (about 300 feet away);
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Credits. This page was last revised on December 14, 2023. It was originally submitted on September 9, 2023, by Devry Becker Jones of Washington, District of Columbia. This page has been viewed 160 times since then and 89 times this year. Photos: 1, 2. submitted on September 9, 2023, by Devry Becker Jones of Washington, District of Columbia.
