File:Backstaff.jpg

Original file(1,024 × 819 pixels, file size: 274 KB, MIME type: image/jpeg)

"The back-staff, also known as the Davis quadrant (called a quadrant because it could measure up to 90º), was the first instrument specifically designed for finding latitude at sea. English explorer John Davis conceived the instrument while on a voyage to find the Northwest Passage and in 1595 described it in his book The Seamen’s Secrets."

Excerpt by Jeanne Willoz-Egnor from http://www.ion.org/museum/item_view.cfm?cid=6&scid=13&iid=31

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current20:30, 25 March 2011Thumbnail for version as of 20:30, 25 March 20111,024 × 819 (274 KB)Sean (Talk | contribs)"The back-staff, also known as the Davis quadrant (called a quadrant because it could measure up to 90º), was the first instrument specifically designed for finding latitude at sea. English explorer John Davis conceived the instrument while on a voyage t
  • You cannot overwrite this file.

The following page links to this file:

Metadata