Last week, I did a small tour for some staff members who were interested in seeing what types of photographic materials we have in our collections. I mostly chose items from the George Davidson collection because it contains several types of photographic processes.
George Davidson was an astronomer, geodesist, and coastal surveyor. In 1868, Davidson was made chief of the U.S. Coast Survey on the Pacific Coast and held that position until June 1895, during which time he oversaw the work of all western survey teams. Davidson was President of the California Academy of Sciences from 1872-1886. He was instrumental in popularizing astronomy on the West Coast and made his private observatory that is featured below, in Lafayette Park, San Francisco available to the scientific community and the public.
Cyanotypes from the Davidson Observatory
For the tour, I pulled various types of photographs including stereopticons, glass lantern slides, glass plate negatives, and cyanotypes.
The cyanotype was invented in 1842 by John Herschel but was most widely used from the 1880s to the 1920s. In this contact printing process, paper is coated with a solution of light-sensitive iron salts. A negative or object is placed on the paper and when exposed to ultraviolet light the chemicals react to form ferric ferrocyanide and ferrous ferricyanide, known as Prussian blue and Turnbull’s blue when used as pigments, and a blue image appears. Once the desired image is acquired the solution is washed away. This is the same process used in making blueprints. Because cyanotypes continue to be light-sensitive after their creation, they should be stored in the dark to prevent fading and damage.
6.4 inch Alvin Clark telescope in the Davidson Observatory
While this process was never very popular for photography, we have several cyanotypes in our manuscript collections including the Alice Eastwood and Barton Warren Evermann Collections.
Archives and Digital Collections Librarian
Children admire Apollo 11 lunar sample at the Academy in 1970. N2579D, Copyright California Academy of Sciences Library, Special Collections. Photo by Lloyd Ullberg.
Today is the 40th anniversary of the liftoff of Apollo 11, the first manned mission to land on the Moon. Four days later, on July 20,1969, Neil Armstrong and Buzz Aldrin became the first human beings to walk on the lunar surface.
But what does that have to do with the Academy Library? Believe it or not, several things:
This is the first post on the Academy Library’s new blog. After days of debating what the first post should be about, the commemoration of such an incredible scientific and technological achievement seems like a no-brainer for kicking off the blog.
One of the reasons I started this blog is that people ask me all the time, “What do librarians do all day?” or “Why do we need libraries anymore?” One answer to these questions is that libraries are a fantastic venue for interesting research and projects that might not fit in at other institutions. Librarians are in the business of finding, collecting, categorizing, and preserving information, and finding ways to share that information with other people. We do this in a variety of ways, including our library catalogs and archival finding aids. Another way libraries share information with the masses is through the development of exhibits or other projects, like this one from the John F. Kennedy Library and Museum, which happens to be about the Apollo 11 mission http://www.wechoosethemoon.org. You can follow the activities of the Apollo 11 mission in real time, with historic archival footage and images. Click on the URL to see what phase of the mission was unfolding exactly 40 years ago right now.
The California Academy of Sciences once hosted a piece of Apollo 11 history: a moon rock, collected by Neil Armstrong at Tranquility Base in July 1969. The photograph above was taken while the lunar sample was on exhibit at the Academy in the summer of 1970. The lunar sample currently on exhibit at the Academy is from a 1972 mission.
Be sure to tune in to http://www.wechoosethemoon.org at 10:56 pm EST on July 20th to see how the Kennedy Library and Museum reenacts Armstrong’s walk on the moon. Then come to the Academy and look at our moon rock. Tell ‘em the Librarian sent you.