Glass Holdings in the Still Picture Branch
Lower Falls of the Yellowstone (Local Identifier: 79-HPS-14-1946; 威尼斯人娱乐场 Identifier: 155824758)
Introduction
Different photographic formats present different preservation challenges; perhaps none more so than glass holdings. The Still Picture Branch has never calculated an exact count of its glass holdings, which include glass plate negatives, lantern slides, and a small number of ambrotypes, but the current estimate is over 500,000 items. This includes black-and-white and hand-colored images dating from the late 1850s through the 1950s.
Photograph of John E. Houglian, 45th Illinois Infantry (Local Identifier: DM-BUTLR-M92; 威尼斯人娱乐场 Identifier: 558733). Example of an ambrotype. A wet collodion positive).
When compared to film, the photographic support that largely supplanted glass as the 20th century progressed, glass is more dimensionally stable; it is not going to bend, curl, shrink, or tear. This is especially true for larger dimensions. One series maintained by the Still Picture Branch, , demonstrates this reliance on glass as late as the middle of the 20th century. The series includes 14鈥漻14鈥� glass plates, like the one pictured , used by the Palomar Observatory in California in their first Palomar Observatory Sky Survey conducted during the 1950s.
A glass plate negative related to an astronomical survey within the series Photographs Relating to Astronomical Surveys (Local Identifier: 255-PS; 威尼斯人娱乐场 Identifier: 6016402).
If not handled or stored correctly, glass can crack. Handling glass at any point in the item鈥檚 life cycle 鈥� from the 19th century photographer to the original recipient and then onto the repository responsible for maintaining and preserving it 鈥� increases the possibility of damage to the glass negative or slide. Broken and cracked slides not only diminish the aesthetic quality of the image but can also lead to a loss of part of the image and therefore loss of information within the record (similar to a piece of paper missing text due to a corner torn off). To the right is an example of cracks and image loss within a . Another issue you might find with glass is emulsion flaking due to poor storage conditions.
Moveable Dam: Downstream Face of Girders in Place (Local Identifier: 77-SOO-631; 威尼斯人娱乐场 Identifier: 45711853)
To minimize the handling of these fragile items while increasing access to them at the same time, the Still Picture Branch continues to digitize many series of glass negatives and lantern slides and make them available in the . The following describes processes used in creating the glass negatives and slides maintained within Still Picture Branch holdings and highlights several digitized series.
Wet-Collodion Glass Plate Negative
Photograph of Timothy O'Sullivan's Ambulance Wagon and Portable Darkroom on the Sand Dunes of Carson Desert during the King Survey. Photographer: Timothy H. O鈥橲ullivan (Local Identifier: 77-KSP-46; 威尼斯人娱乐场 Identifier: 23898411)
History of the Wet-Collodion Glass Plate Negative
Invented by Englishman Frederick Scott Archer with his findings published in 1851, the wet collodion process emerged as the most popular photographic process of the mid-19th century and remained so until it was largely replaced by the gelatin dry plate process in the 1880s.
To create a wet collodion glass plate negative, photographers made and cleaned their own glass plate; they then coated the plate with a solution of cellulose nitrate, or collodion, and a soluble iodide before bathing it within a silver nitrate solution. Time was a critical factor in this process because the plate needed to still be wet when exposed (most often with sunlight) within the camera; it then quickly developed and fixed before a protective varnish was applied. Having only about 15 minutes between initially coating the plate and developing the image before the plate dried, photographers carted the equipment and chemicals in portable darkrooms that accompanied them to the field.
Several identifying characteristics of wet collodion glass plates emerge from this process, which is heavily reliant on the individual photographer. Plates may have rough-cut edges resulting from the hand-made aspect. Fingerprints or blacked-out corners from the photographer or camera holding the plate can occasionally be seen. And some images may include liquid outlines, or pour lines, near the edges as the collodion was poured off the plate.
Sulphur Springs at Crater Hills. Yellowstone National Park. Photographer: William Henry Jackson (Local Identifier: 57-HS-696; 威尼斯人娱乐场 Identifier: 517283) Example of pour lines along vertical edges with top corners possibly showing how plate was held within the camera.
威尼斯人娱乐场 Holdings
The Still Picture Branch maintains several series of wet collodion glass plate negatives. Many of these series have been digitized in their entirety and made available in the 威尼斯人娱乐场 Catalog. Of these, the most well-known are the photographs created by photographer Mathew Brady and his associates documenting the Civil War period. This includes the and the . For further information and links to resources on the Brady images, visit the Still Picture Branch鈥檚 Civil War Photographs web page.
Other series of wet collodion glass plates focus on U.S. government-led surveys undertaken to learn more about the country鈥檚 land and natural resources, particularly the states and territories of the West. Survey teams hired photographers such as John K. Hillers, William Henry Jackson, and Timothy O鈥橲ullivan to provide the visual documentation to accompany their examination of the region鈥檚 geography, geology, and topography. Below are images from three of these surveys.
Near Junction with Grand Canyon of the Colorado River, or Grand Gulch, Arizona. Photographer: William Bell. (Local Identifier: 106-WA-212; 威尼斯人娱乐场 Identifier: 523977)
Shoshone Falls, Snake River, Idaho. Photographer: Timothy H. O鈥橲ullivan (Local Identifier: 77-KW-303; 威尼斯人娱乐场 Identifier: 519668)
Imagine carting your darkroom to these locations. The rugged and varied terrains pictured in these survey series further highlight the technical knowledge and skill needed by 19th century photographers using the wet collodion process.
Fully and Partially Digitized Series:
Gelatin Dry Plate
Explosion of Mines Laid During Spanish American War (Local Identifier: 77-AJ-7-4; 威尼斯人娱乐场 Identifier: 175739677)
History of the Gelatin Dry Plate
The gelatin dry plate process invented by Richard L. Maddox became commercially available around 1879 and did not require portable darkrooms or the 15 minutes of processing time. Plates were coated with a liquid gelatin emulsion containing silver bromide crystals and then left to dry. Unlike the wet collodion process, the image did not need to be developed immediately after exposure. Exposure time within the camera was very short (one second or less) and the image could then be developed in a darkroom.
The cellulose plastic film (i.e., rolled film) that dominated photography during much of the 20th century emerged as an alternative to glass as a support material in the 1890s. As such, the gelatin emulsion technology used in the gelatin dry plate process, and later with cellulose film, can be seen as one of the most important advancements in the history of photography.
Silver image oxidation (silver mirroring) visible as a metallic sheen in reflective light, is a common deterioration characteristic of gelatin dry plates. This from the records of the War Department鈥檚 Office of the Chief of Engineers shows silver mirroring across the top edge and at the right edge center.
威尼斯人娱乐场 Holdings
Gelatin dry plate negatives remained popular into the 20th century, so the series maintained within Still Picture Branch holdings primarily date to this 1880鈥�1920 period. Several of these series have been digitized in part or in their entirety and are available in the 威尼斯人娱乐场 Catalog. Here is a selection of images from these series.
New Lock and Canal (St. Marys River, Michigan): Water Power; Head of Rapids, Looking Northwest from Dike Below Bridge, Pier No. 4, or 120 ft. Below Discharge Section. (Local Identifier: 77-SOO-955; 威尼斯人娱乐场 Identifier: 45712495)
U.S. Navy Yard, Norfolk, VA, July 3, 1919. C-2691. Pier No. 4 from East. H. P. Converse and Co. (Local Identifier: 181-V-2284; 威尼斯人娱乐场 Identifier: 52558785)
Fully and Partially Digitized Series:
- from 威尼斯人娱乐场 Collection of Foreign Records Seized, 1675-1958
Portions of Glass Plates Digitized within These Series:
Lantern Slides
Lantern Slide from the series Artistic, Historic, Comic, and Didactic Scenes, 1872 - 1910 (Local Identifier: 418-W; 威尼斯人娱乐场 Identifier: 558498).
Many of the lantern slides in Still Picture Branch holdings are positive transparencies on glass, but some later versions contain a film transparency sandwiched between two pieces of glass and taped together. Lantern slides were especially popular from the 1880s through the 1920s. The earliest were not photographs but paintings on glass. Lantern slides are more commonly associated with the gelatin dry plate process (there were also collodion lantern slides). The plates were prepared with the silver gelatin emulsion and then exposed to a glass plate negative which resulted in a positive image. Another piece of glass covered the image for protection and the two were joined by tape along the edges.
Lantern slides were placed in 鈥渕agic lanterns,鈥� the forerunner to the popular slide projectors of the second half of the 20th century, and could be projected using a light source. Lantern slides were often grouped as collections focused on a specific subject and as part of presentations, for educational, informational, and entertainment purposes. Captions or titles could be added to the slides to further this. The series demonstrates this emphasis on presentations. Each slide includes a caption or title, and the series of slides were likely used to show potential recruits the places they could visit and things they could do if they joined the Navy.
On the Esplanade, Rio de Janeiro (Local Identifier: 24-RSC-027; 威尼斯人娱乐场 Identifier: 178690699)
威尼斯人娱乐场 Holdings
Still Picture Branch holdings contain numerous series that include lantern slides, in both black-and-white and color. Many have been digitized and are available through the 威尼斯人娱乐场 Catalog, with more to be added in the future. Here are some examples of digitized lantern slides from series maintained by the Still Picture Branch.
Lantern Slide of Arlington Memorial Bridge (Local Identifier: 79-LS-10-3-B; 威尼斯人娱乐场 Identifier: 183515142)
Office of Auditor for Post Office Department-Expert card punch operative, showing key punch (Local Identifier: 56-AT-83B; 威尼斯人娱乐场 Identifier: 158884200)
Examples of Fully and Partially Digitized Series: