Box-folder 55:6

Scope and Contents From the Sub-Series: Organized under three headings. The first is Design and Calculations for various telescopes, including speculative designs never constructed. The second heading, Grinding, Polishing, and Figuring Records, contains notes regarding work done by Tombaugh on mirrors for his personal telescopes, as well as others' telescopes. The final heading, Miscellaneous, includes correspondence and other records regarding supplies for telescopes, correspondence related to the "16-inch Club" started by Tombaugh...