New York, American Telephone and Telegraph Company, 1927. Lex8vo. Volume VI, July, No. 3, 1927 of "The Bell System Technical Journal". In the original printed blue wrappers. A bit of browning to spine and extremities, but overall fine. Internally very nice and clean. Pp. 461-494. [Entire issue: Pp. 375-550].
First publication of Molina's fundamental discussion on the problems concerning telephone trunking problems.
"If telephone plants were provided in such quantities that when a subscriber makes a call there would be immediately available such switching arrangements and such trunks or paths to the desired point as may be necessary to establish the connection instantly, it would require that path and switching facilities be provided to meet the maximum demand occurring at any time, with the result that there would be a large amount of plant not in use most of the time." (From the introduction to the present paper).
"Edward C. Molina, a self-taught researcher, made seminal contributions to telephone traffic theory. [...] There were early attempts to use probability theory for the analysis of exchange" (Gass, An annotated timeline of operations research, 2005, p. 35.). His 1928 book on congestion theory became the classic text on the subject. The present paper anticipates many of the themes and problems presented in that book.
Other papers of interest contained in the present issue:
1. Ferguson, J.G. Measurement of Inductance by the Shielded Owen Bridge. Pp. 375-386.
2. Gilbert, J.J. Determination of Electrical Characteristics of Loaded Telegraph Cables. Pp. 387-401.
3. Clokey, A.A. Automatic Printing Equipment for Long Loaded Submarine Telegraph Cables. Pp. 402-424.
4. Curtis, Austen M. The Application of Vacuum Tube Amplifiers to Submarine Telegraph Cables. Pp. 425-441.
5. Peterson, Eugene; Evans, Herbert P.Modulation in Vacuum Tubes Used As Amplifiers. Pp. 442-460.
6. Carson, John R.; Hoyt, Ray S.Propagation of Periodic Currents Over a System Of Parallel Wires. Pp. 495-545.