File:Sumner - circle of equal altitude.jpg

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Summary

DescriptionSumner - circle of equal altitude.jpg	English: Discovery of the circle of equal altitude - A New and Accurate Method of Finding a Ship's Position at Sea, by Projection on Mercator's Chart, Capt. Thomas H. Sumner, July 1843, Thomas Groom & Company of Boston
Date	1843
Source	A New and Accurate Method of Finding a Ship's Position at Sea, by Projection on Mercator's Chart, Capt. Thomas H. Sumner, July 1843, Thomas Groom & Company of Boston
Author	Capt. Thomas H. Sumner

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