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In 1874 and 1882, the US Naval Observatory (USNO) sent multiple teams to time the transit of Venus with the aid of photographic equipment.  Expedition photographs reproduced here are in the collection of the US Naval Observatory Library.  

sawhorse 1415	whaler 01416	skiff 01419	seal 01430
camp	boy 01418	sighting 01423	5observers
man 01417	observatory 01429	tripod 01431	anchor
hutfield	brooklyn 01406	practice_obs 01401	ship 01402

The images below were digitally photographed at an open table, so the quality is somewhat compromised and reflections occasionally appear.  That said, most of the pictures to which you can link remain as large jpeg files.

patagonia 1405	macabre 01412	wiring 01425	station 01411
vladivostok 01407	scope inside 01414	brickhouse 01426	low-water 01413
instrument 01393	barrel_seat 01420	inlet 01427	group 01389
rig 01410	bird 01421	vlads 01408	helio 01392
heliometer 01395	multihuts 01397	helio_pier 01399	old_site 01400
tent 01403	waterside 01437	bighat 01436	couple 01435
barrelrack 01434	stump 01433	chatham_shed 01432

	Additional images from the George Eastman House Still Photograph Archive are available at http://www.geh.org/ar/strip47/htmlsrc/lanternsld_sum00040.html.  Shown is "Transit of Venus Huts erected at Naval Observatory; transparency, collodion on glass."
	http://justfurfun.org/astrohtml/heliostat.htm  An original heliostat from the USNO expeditions; in a private collection.
	Diagrams of heliostats from the USNO expeditions; images provided by Robert Havlik.

Below are images of the US Naval Observatory in Washington, D.C.

Additional USNO artifacts can be viewed at http://216.239.51.100/search?q=cache:bHpjbTa1IUcJ:www.usno.navy.mil/library/artwork/artwork.html+transit+of+venus+1874&hl=en&ie=UTF-8.

The following text and images are courtesy of the U.S. Naval Observatory Library; used with permission.

Transit of Venus Plates

Images from photographic plates of the Transit of Venus (Venus crossing the face of the Sun), a very rare phenomenon that last occurred in 1874 and 1882. Wet bromo-iodide plates were used in 1874, but by 1882 dry collodion emulsion plates were available. The Naval Observatory and Transit of Venus Commission sent 8 parties around the world to observe each of the transits; the results were important for determining the scale of the solar system. Only 11 plates survive from the American 1882 expeditions; none of the plates from the American 1874 transit expeditions has survived. The next transits of Venus occur in 2004 and 2012.  

For details of and more images from the 19th century USNO expeditions, either buy "The U. S. Naval Observatory And the American Transit of Venus Expeditions of 1874 and 1882," Sky and Ocean Joined:  The U. S. Naval Observatory, 1830-2000 by Steven J. Dick (Cambridge University Press, 2003), or see online Chapter 7 from the book. 

Thanks go to Brenda Corbin and Steven Dick for their kind assistance at the US Naval Observatory.

In preparation for the 1882 transit of Venus expeditions, the United States Naval Observatory printed a publication listing the detailed duties of each member of the expedition team.  (See "Instructions" page.)  Based on the experiences of the 1874 expeditions eight years prior, the book explains what the observer may expect to see and how to discern the instant of contact. 

www.transitofvenus.org

Copyright ©2003-2008 Chuck Bueter.  All rights reserved.