Conservation of Deteriorating Vertebrate Paleontology Nitrate Negatives

Los Angeles County Museum Of Natural History Foundation, Los Angeles CA

Investigators

Abstract

A grant has been awarded to Dr. McLeod at the Natural History Museum of Los Angeles County (LACM) for conservation of deteriorating nitrate negatives of photos taken by the personnel of the California Institute of Technology (CIT) to document collecting of vertebrate fossils, including dinosaurs, during the period 1925-1949. Although standard for photography at that time, nitrate negatives are known to deteriorate and they constitute hazardous materials. These nitrate negatives represent the best, and sometimes the only, documentation of the localities for the CIT fossil vertebrate collections, acquired by the LACM in 1957, and additionally document the conditions in some areas of the western United States during the early 20th century that have subsequently been highly altered due to natural causes or human activities. These nitrate negatives currently range in condition from apparently pristine to almost completely destroyed. Ultimately, they will all deteriorate to an unusable state. Following the National Park Service guidelines for conservation of nitrate negatives, with funding from the National Science Foundation for this project new interpositives, copy negatives, and prints will be made for the 2,043 CIT field photographs. This will preserve the photographic images that otherwise would be lost due to the deterioration of the nitrate negatives. A half-time curatorial assistant will be hired to scan the photographs from the nitrate negatives, type in the descriptions, adjust the images, and place them on the Museum's web site, thereby providing wide access to these images for both lay and professional audiences. A half-time student assistant will be hired and trained to determine the latitude and longitude of the fossil localities represented by the CIT nitrate negative images, thereby providing a new permanent standard reference for the location of the sites. The broader scientific significance of the project is that these photographs document the localities for a substantial and important collection of vertebrate fossils from western North America. Some of the areas documented by these photographs no longer exist due to development in the more than half century since the collections were made. Teaching students how to use modern technology to determine the exact location of the fossil sites represented in the photographs will expand the educational activities of the Museum and enhance the Museum's commitment to education. Providing web access to the images will give a broad and international audience a portal to these early classic fossil vertebrate sites and the collections derived from them.