One of the founding documents of information theory:
Ralph Hartley's 1928 work, "The Transmission of Information"
first printing in original wrappers

What I hope to accomplish in this direction is to set up a quantitative measure whereby the capacities of various systems to transmit information may be compared."

-Hartley, p.535

First printing of one of the foundational works in information theory.

In the opening paragraph of his landmark paper, "A Mathematical Theory of Communication," Claude Shannon credits Hartley's "Transmission of Information" (along with the work of Nyquist) as forming "the basis" for "a general theory of communication." He then explains how he will extend this new theory is his present work. R.V.L. Hartley, a research engineer at Bell Labs and the inventor of the Hartley oscillator, was one of the first to make progress in quantitatively measuring the capacities of various types of information systems to transmit information.

"Hartley distinguished between psychological and physical considerations -- that is, between meaning and information. The latter he defined as the number of possible messages, independent of whether they are meaningful. He used this definition of information to give a logarithmic law for the transmission of information in discrete messages: H = K log sn where H is the amount of information, K is a constant, n is the number of symbols in the message, s is the size of the set of symbols, and therefore sn is the number of possible symbolic sequences of the specified length n. This law included the case of telegraphy and subsumed Nyquist's earlier law." (Aspray, "The Scientific Conceptualization of Information"). In his paper, Hartley had arrived at many of the most important ideas of the mathematical theory of communication: the difference between information and meaning, information as a physical quantity, the logarithmic rule for transmission of information, and the essential concept of noise as an impediment in the transmission of information. Although Hartley, in 1928, was primarily concerned with information transmission in the telephone, telegraph, and television, his work, of course, later became of great importance in the development of the computer. (Pierce, Symbols, Signals, and Noise). Owner signature on front wrapper, slight edgewear and fading to spine. In outstanding condition, most rare in original wrappers.