Photographic Plates

255 photographic glass plate negatives (gelatin dry plates), stored in 23 original plate boxes, haphazardly arranged. All appear to be original plates, mostly exposed in the early 1930s. About half (127) show buildings, telescopes, instruments and people at Boyden Observatory, South Africa, mostly during the early period of construction, thus providing a very valuable historical record. Several of these plates have dates scratched into the glass. Two plates show the observatory as it was at Arequipa in Peru. About a quarter (56) are portraits and group photographs. While many of these are of known astronomers, others show unidentified people and children, often in social settings, helping build a richer picture of life at an observatory. Of interest to general historians may be the small number (24) of scenes taken elsewhere in South Africa, in the 1930s. As far as can be established, these were taken during an expedition to observe a solar eclipse, and during a journey to the Royal Observatory, Cape of Good Hope. There are 41 images of astronomical objects, including a series of cloudscapes and of a lunar eclipse. Three images of the 74-inch Radcliffe Telescope in Pretoria, and one of an alert cat cautiously regarding a puff adder, round out the collection. The old plate boxes in which the plates were found often contain pencilled titles, but it is clear that some plates have been returned to incorrect containers over time, and the collection is now jumbled. Taken as a whole, it can be assumed that an expedition was mounted in 1940 to photograph the solar eclipse from Murraysburg, with a specially built multiple-camera device on which was mounted the 5-inch Voigtländer and 1.5-inch Ross lenses. n/a. Extent: 255 plates, in 22 plate boxes. Size and dimensions of original material: Plates (height 8.2 cm, width 10.7 cm, thickness 0.3 cm) in plate boxes (height 11 cm, width 14 cm, thickness 3 cm). Condition of original material: Glass substrate in stable condition, although most plates have small chips along the edges. There is no delamination of the emulsion, but all plates exhibit silver mirroring particularly around the edges. Custodial history: N/a. Arrangement: N/a. Alternative calendar and date: N/a, N/a Author(s)/Creator(s): English. Scribe(s): Latin. Publisher(s): Left-to-Right. Editor(s): Unrestricted. Volume number: N/a. Original institution reference: PLB.