Sally Crawford, a director of the HEIR (Historic Environment Image Resource) project at the Institute of Archaeology at the University of Oxford, gave a fascinating overview of the lantern and glass slide photographs in the Resource. These slides, dating from the late 19th and early 20th centuries, were used as a teaching resource at the university, allowing for the first time simultaneous viewing and discussion of images by class-sized groups. The images are particularly rare as they were captured at a time when photographic equipment was bulky, travel difficult and processing inconvenient. From the 1940s and 1950s, with the advent of 35mm slide photography, they were no longer used for their original purposes, became neglected and were even threatened with destruction.
The Resource mainly covers material of interest to archaeologists, anthropologists and art historians, although the inclusion of people, vehicles etc offers subjects important to other people. The slides often show excavations in progress and sites and buildings which have since been destroyed. For example, one taken in 1907 shows the windmill in Nettlebed (illustrated), which burned down in 1912 and another taken in 1932 shows the Congregational Church in Witney which was demolished to make way for a supermarket in 1969.
The HEIR Project aims to produce digital images from the glass slides (and to conserve the originals) and to index these images to provide a searchable resource. It is looking for help from the public to do this. You can view them at http://heirtagger.ox.ac.uk and use your own skills and knowledge to index these beautiful and fascinating images yourself. You can also help by providing present-day images corresponding to those on the slides, using an iPhone app (Android version is being developed).