Cyanotypes - so named for the distinctive blue cast to the printed images - were first introduced by John Herschel in 1842. Though cyanotypes would not reach the height of their popularity until the mid-1880s, British botanist and photographer Anna Atkins used cyanotype paper to document British algae, specifically seaweeds, by placing unmounted, dried algae directly on the cyanotype paper. These images appeared in her self-published book, Photographs of British Algae: Cyanotype Impressions. Though never published commercially, Atkins work is believed to be the first book illustrated with photographic images.

To create a cyanotype, paper was coated in a light-sensitive solution, the original solution being a formula of potassium ferricyanide and ammonium ferric citrate. When the paper had dried, a negative was placed on top, and exposed to light. Thus exposed, the ferric salt on the paper became ferrous salt, and the ferrous salt, in turn, reacted with the ferricyanide to produce a distinctive blue color. Any ferric salts shielded from the light source by the negative remained unchanged, and were washed away at the rinsing stage, allowing the white of the paper to show through. The process is also know as "blue-printing" (Ritzenthaler, et.al., 33-34).

Horticulture Department Photographs, 1900-1980
The Horticulture Department Photographs consist of images taken and assembled by horticulture faculty for teaching and research and depict a variety of horticultural topics as well as the Oregon Agricultural College campus. The Department of Horticulture and Botany was established in 1888; a separate Horticulture Department formed in 1909. Images from this collection have been digitized and are available in Oregon Digital. Boxes 31 and 32 contain photograph albums that include cyanotype prints.

E.E. Wilson Photographic Collection, 1855-1953
The E. E. Wilson Photographic Collection consists of images of Wilson, a Corvallis native and Oregon Agricultural College (OAC) alum, as well as his family and friends, the OAC campus, Corvallis, and other locations around the Pacific Northwest. The collection also includes images of the 1915 Panama Pacific Exposition in San Francisco and photos of Siletz tribe members.
Boxes 02 and 04 contain cyanotype prints (Image #0489 and 1245).

William L. Finley Papers, 1899-1955
The William L. Finley Papers document the wildlife conservation work of Finley and his wife Irene, and the photography work of Herman T. Bohlman, who worked with Finley in the first decade of the 20th century. Finley was a photographer, filmmaker, and author who wrote and lectured extensively on wildlife conservation issues. The collection includes published and unpublished manuscripts, lecture and field notes, reports, correspondence, photographs, and motion picture films. Manuscript items and photographs from this collection have been digitized and are available in Oregon Digital. All of the films held in the collection are also available online. The collection includes a single cyanotype in Box-folder 17.13 (Item #38).

Extension Service Photographs, 1900-2007
The Extension Service Photographs document Extension programs, activities, and staff throughout Oregon as well as Oregon agriculture. The Extension Service was established in Oregon in 1911. Images from this collection have been digitized and are available in Oregon Digital. Box-folder 1.1 contains a cyanotype (Item #040).

William F. Groves Photographs, 1888-1942

The William F. Groves Photographs are comprised of photographs assembled by William Franklin Groves throughout his life in Corvallis, and his time as a student at Oregon Agricultural College. Groves graduated from Oregon Agricultural College in 1897 with a degree in Mechanical Engineering.  Images from this collection have been digitized and are available in Oregon Digital. The collection includes a single cyanotype: Item #10.

• Cyanotypes in Oregon Digital