Certain Factors Affecting Telegraph Speed in Bell System Technical Journal 3 No. 2 pp. 324-346, April 1924 ["ONE OF THE FOUNDATIONS OF INFORMATION THEORY," Original wrappers]

New York, 1924. 1st Edition. FIRST EDITION IN ORIGINAL WRAPPERS OF "ONE OF THE FOUNDATIONS OF INFORMATION THEORY" (Claude Shannon, A Mathematical Theory of Communication, 1948). Beginning with this lengthy twenty-two page paper (see Origins of Cyberspace 163), Nyquist's nascent work ferreting out the necessary bandwidth requirements for the transmission of information was foundational and it was critical to and enabled Shannon's development of information theory. NOTE that we separately offer Nyquist's second paper, Certain Topics in Telegraph Transmission Theory as well.

Nyquist's work studied the relationship between the speed of a telegraph system and the number of signal values employed by that system. His efforts established the principles by which continuous signals could be converted into digital signals and provided "the first statement of a logarithmic law for communication" (Stanford Encyclopedia of Philosophy). Nyquist was "the first to express the amount of ‘intelligence' that could be transmitted given a certain line speed of a telegraph systems and [to do so] in terms of a log function" (Origins of Cyberspace 343). Nyquist's work was also "the first examination of the theoretical bounds for ideal codes for the transmission of information" (ibid).

In 1924 and while working at Bell Telephone Laboratories, Harry Nyquist's work centered upon the obvious need to improve the speed with which data transmission was carried over the wires. "In considering methods for increasing the speed of telegraph circuits [he wrote], the engineer is confronted by the problem of transmitting over a circuit the maximum amount of intelligence using a given frequency range, without causing undue interference, either in the circuit being considered or from that circuit to other circuits" (Nyquist, 1924).

In the paper offered here, Nyquist considered "two fundamental factors entering into the maximum speed of transmission of intelligence by telegraph. These factors are signal shaping and choice of codes. The first is concerned with the best wave shape to be impressed on the transmitting medium so as to permit of greater speed without undue interference either in the circuit under consideration or in those adjacent, while the latter deals with the choice of codes which will permit of transmitting a maximum amount of intelligence with a given number of signal elements" (Nyquist 324). CONDITION & DETAILS: Quarto. (9 x 6.25 inches; 225 x 156mm). Complete issue in original paper wrappers; repaired at the spine and edges of front wrap; library stamp on front wrap and the first page of text (not the Nyquist paper). The issue is internally in fine condition, bright and clean throughout. The issue is housed in a custom clamshell case of blue linen, gilt-lettered at the spine. Very good condition.