#cross-staff

[allegorypaintings]

Allegory of Navigation with a Cross-Staff

Artist: Paolo Caliari Veronese (Italian, 1528-1588)

Date: 1555-1560

Medium: Oil on canvas

Collection: Los Angeles County Museum of Art, Los Angeles, CA, United States

[historysurvivalguide]

The description and use of the sector, crosse-staffe, and other instruments : with a canon of artificiall Sines and Tangents, and the use thereof in astronomie, navigation, dialling and fortification by Edmund Gunter (1636)

A simple device to measure angles in sky. By measuring the angle between the horizon and Polaris an observer can determine their latitude

[marryat92]

"We are unfortunate in thus parting with all our consorts," observed Mynheer Kloots to Philip, as they were standing at the gangway; "but it must be near meridian, and the sun will enable me to discover our latitude. It is difficult to say how far we may have been swept by the gale and the currents to the northward. Boy, bring up my cross-staff, and be mindful that you do not strike it against anything as you come up."

The cross-staff at that time was the simple instrument used to discover the latitude, which it would give to a nice observer to within five or ten miles. Quadrants and sextants were the invention of a much later period. Indeed, considering that they had so little knowledge of navigation and the variation of the compass, and that their easting and westing could only be computed by dead reckoning, it is wonderful how our ancestors traversed the ocean in the way they did, with comparatively so few accidents.

— Frederick Marryat, The Phantom Ship