BSTJ 1: 1. July 1922: The Nature of Speech and Its Interpretation. (Fletcher, Harvey)
A technical paper by Harvey Fletcher published in the first issue of the Bell System Technical Journal in 1922, written for telephone engineers and researchers studying hearing and speech transmission. The plates are engineering line graphs on ruled grids — articulation and energy curves against frequency, loudness scales marked in napiers, a tangle of twenty overlaid audiograms, and a V-shaped vowel chart labelled with words like tool, tape and tar — useful for grid textures, hand-lettered curve labels and diagrams of the voice.
