signalflags
8 photos tagged signalflags, from 7 members of Flickr Commons.
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- weather
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- pharmacists
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- victoriantradecards
- miamiuniversitylibraries
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Members using this tag
- Miami University Libraries - Digital Collections
- The Library of Congress
- SDASM Archives
- Australian National Maritime Museum on The Commons
- State Library of Queensland
- Florida Memory
- Library Company of Philadelphia
Photos
Photos tagged signalflags:
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Recent uploads
The last upload was March 2019.
Flags flying at the Windmill Tower, Brisbane, Queensland, ca. 1910 from State Library of Queensland uploaded March 2019
Men Wanted for the Army [Radio] from Library Company of Philadelphia uploaded May 2017
AL_005A_122 from SDASM Archives uploaded September 2013
Army signal corps soldiers during the Spanish-American war from Florida Memory uploaded April 2009
Dr. J.C. Ayer & Co. from Miami University Libraries - Digital Collections uploaded December 2008
Dr. J.C. Ayer & Co. from Miami University Libraries - Digital Collections uploaded December 2008
Signalling from cash register bldg. - Dayton (flood) (LOC) from The Library of Congress uploaded September 2008
Conversations
Here’s a selection of the conversations happening on these photos:
Navy Sea League Cadets with signal flags at Snapper Island in Sydney
- afiq arifin said:
- Alexander McCall said:
- Australian National Maritime Museum on The Commons said:
Army signal corps soldiers during the Spanish-American war
from Florida Memory
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signal mirror said:
Heliograph: The two tripods held by the two soldiers at right comprise a US Army Signal Corps heliograph - a tripod-mounted device for sending messages by flashes of sunlight using Morse or Myer code, with a range up 30 miles or so. This heliograph is set up in duplex, or "dual-mirror" mode, the mode used when the sun was behind the signalers. The job of the dark-suited soldier at the extreme right was to keep the sun beam reflected by the dual 4.5 inch square mirrors on his tripod in constant alignment on the target as the sun moved, using vernier elevation and azimuth screws. The job of the light-suited soldier in the middle was to open and close the shutter flap on his tripod to produce the dots and dashes of the code. A diagram showing this heliograph (albeit in single-mirror mode), taken from [1], is here (click on the thumbnail to magnify), and see [1] for the dual-mirror mode diagram.
An 1893 photograph of this type of heliograph (albeit in single-mirror mode), taken from [2], is here (click on the thumbnail to magnify)
To learn more about heliographs, you can read [1] and [2], as well as this Wikipedia article:
en.wikipedia.org/wiki/Heliograph
You can also see this Flickr gallery (click on the thumbnail):
[http://www.flickr.com/photos/signalmirror/galleries/72157630246445306/]
and this set (click on the thumbnail) : (Historical Photographs of American Heliographs)
[http://www.flickr.com/photos/signalmirror/sets/72157631040759962/]
[ 1 ] Annual Report of the Chief Signal Officer of the Army to the
Secretary of War for the Year 1888, Government Printing Office, 1889
The new standard heliograph is discussed in Appendix I, pp. 42-47,
and depicted on page 46, here:
books.google.com/books?id=E2nPAAAAMAAJ&pg=PA46&dq...
[2] "The Heliograph", The Compass, Vol. II, No. 11, June 1, 1893, page 161
books.google.com/books?id=tX0SAAAAYAAJ&pg=PA161 -
Florida Memory said:
signal mirror Thanks for the great information!
Flags flying at the Windmill Tower, Brisbane, Queensland, ca. 1910
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Aussie~mobs said:
This photo used in the Coloured Shell Series of postcards produced between 1905 and 1915:

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State Library of Queensland said:
Interesting. We have a black and white version. hdl.handle.net/10462/deriv/96163