Show Business: Acrobats on Trapeze and Wire Typescript notes for lecture on the theme 'Show Business: Acrobats on Trapeze and Wire.' The notes are undated, but reference to several Anthropological Museum collections might suggest that they date from his post-retirement period (1964 - 1980), when Lockhart spent more time on the museum collections. Lantern slides: numbered set of 41 slides (some missing, some numbers duplicated - 39 remain) and 18 un-numbered slides to illustrate the lecture. Glass negatives: Four small boxes containing 79 negatives of images used to illustrate the lecture. These images differ from the extant lantern slides described above. Undated