Volume 13, No. 1
November 2000

Mercurial Matters

Annual Meetings

Letters to the Editor

Urban Legends & the Challenges of Standardization

Paul Israel Wins Dexter Prize

Email & Website Report

An Artificial Line, or Technology as Spectrology

A Daemon in Her Shape

Lincoln Labs Turns 50

Vogue Picture Records

Media Ecology Book Awards

Contact Us

mercurians back button

What is an Artificial Line Circuit?

See related photo and caption

Back to story

An artificial line circuit was an analog of a real line with respect to its electrical characteristics (resistance, inductance, and capacitance). It could work as a regulator (on line) or as a computer (off line). The quality of its construction and the choice of the way it connected to a real line determined the degree of approximation to a real line. The extent of that approximation, in turn, determined the success of regulation or computation. In computing, an artificial line connected to a real line via a mental circuit consisting of a mathematical table, a graph, or a function. In regulating, it connected via an actual circuit in an arrangement that we would now call “negative feedback.” The feedback was that part of the real circuit’s outgoing flow that returned as an incoming flow after traversing the circuit of the artificial line. It was a negative feedback because the purpose of the feedback was to negate whatever part of the incoming flow ought not to be transmitted. We then can call the artificial line an electrical regulator of an electric circuit that functioned similarly to the steam-engine governor—a mechanical regulator of a mechanical circuit, and to the negative-feedback amplifier—an electronic regulator of an electronic circuit. In this sense, the artificial line can be considered as an example of a regulator of the electrical era. The accompanying essay describes the early stages of the artificial line circuit in which it worked as a regulator rather than as a computer.