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Posts Tagged ‘Benchmark’

Antique Scientific Instruments in the US Geological Survey Museum

Posted by havealittletalk on May 11, 2010

First, a question. Tonight when I opened this site using IE, most of the pictures for my last post didn’t load. They did load on Firefox, however. Is anyone else having trouble?

When I was working on the Lesser Known Volcanoes of the USA post, I thought I’d have a look around the US Geological Survey’s Multimedia Gallery. It took me a little time to figure out how to navigate it. When you get to the Gallery’s homepage, you will find three divisions: Photography, Video, and Audio. For each a recent collection is highlighted. For example, tonight in Photography, Gulf of Mexico Oil Spill – Landsat is featured. Clicking on the image gets you to that collection alone. To see what other images are available, you need to go to Browse by or View all.

Choosing Browse by Collections for Photography, you’ll find 21 collections. The number of pictures in each varies widely, from just 2 in National Parks to 913 in Natural Hazards.

Tonight’s posts are a selection of the 152 photos in the USGS Museum section. I have used the captions provided by the USGS staff as well. Unless otherwise noted, the photographer is listed as USGS Museum Staff. All are public domain, but the USGS asks that a credit line is given: Credit: U.S. Geological Survey, Department of the Interior/USGS, and photographer, if named.

I never knew what a benchmark was until I saw these pictures: read on.

Quintant Sextant or Lattice Sextant

Description: This instrument was manufactured by Spencer, Browning & Rust, London. A sextant is used for measuring the altitude of the sun or another celestial body; such measurements can then be used to determine the observer’s geographical position or for other navigational, surveying, or astronomical applications. Dating from the 1820s-1850s, this instrument is among the earliest objects in the U.S. Geological Survey museum collection. Object ID: USGS-000220

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Posted in Historical, US Geological Survey | Tagged: , , , , , , , , , | 2 Comments »

 
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