A collection of newly digitized glass lantern slides, showing early 20th century paleontological digs and the preparation of fossils for display, is now available to the public from the Smithsonian Institution Archives and the National Museum of Natural History.

Taken between 1900 and 1931, the images date from pre-PowerPoint times, when glass lantern slides were the preferred way for researchers to share images. Glass lantern slides were introduced in 1849, about 10 years after the invention of photography. They made it possible for large crowds to view images, rather than a few people at a time. Slides changed photography from an intimate art form to an educational and lecturing tool.

Several of the slides collected here show expeditions in the western United States, led by paleontologists Erwin Hinckley Barbour, J.L. Wortman and James William Gidley. Today, the most is known about Gidley, according to sources in the Smithsonian’s paleontology department.

Gidley initially worked at the National Museum preparing fossils for exhibit. In time, he became assistant curator of mammalian fossils, holding the position from 1911 to 1931. Gidley gained fame for his work on early mammals, especially horses, at a time when the evolution of early mammals was a novel topic for paleontologists.

“He spent a lot of time in the field as a curator, doing very detailed field work,” said Thomas Jorstad, an information specialist for the paleontology department at the Smithsonian. “And he was known for being a genial, cordial and helpful man.”

Jorstad is building comprehensive database for these and other images, which will eventually be available online to researchers and the public. They may, he said, be of more than historical or nostalgic value.

“Comparing what historic sites look like now to old photographs helps people track geological changes,” Jorstad said. “We may see a river widen, or a mountain move.”

The photographs may also guide modern paleontologists to new fossils, Jorstad said. The third image in the gallery, for example, shows two men (probably Gidley and a colleague) with a wagon. It could be useful for people doing field work in the area.

Knowing where fossils were found in the past might help them decide where to dig. It could also help them correlate strata between areas, or determine the age of rocks.

“Geologically they have value,” said Jorstad. “And aesthetically they are very cool, showing what the early days of field work were like.”

Curating the images occupied Jenny Mathias’ summer internship with the Smithsonian’s Field Book Project. The project’s goal is to share an inside view of what it is like to do field research.

Warm-Blooded Vertebrates, co-authored by Gidley and published in 1931, is available for download through the Biodiversity Heritage Library.

Above:

A hand-painted lantern slide shows Erwin Hinckley Barbour, J.L. Wortman and James William Gidley on a paleontological expedition for the Smithsonian Institution’s Division of Vertebrate Mammals. The slide is part of a collection taken between 1900 and 1935 at the Grand Canyon and other unnamed locations in Arizona's Painted Desert, showing the excavation and transport of dinosaur footprints.

Image: Record Unit 424, image # SIA2011-1415/Smithsonian Institution Archives.