Within the mid-Twentieth century, HSNY’s books had been principally technical. Some instance titles from these lists are: Moritz Immisch, “Prize Essay on the Stability Spring” (1872); R. H. Playtner, “An Evaluation of the Lever Escapement” (1895); and Walter Kleinlein, “Guidelines and Apply for Adjusting Watches” (1920). Afterward, the library added extra fashionable titles together with B. Humbert, “The Chronograph, its Mechanism and Restore (1953), and a number of books about newer applied sciences together with F. Hope-Jones, “Electrical Timekeeping” (1949).
