The technical evolution of Vannevar Bush's Memex

This article describes the evolution of the design of Vannevar Bush's Memex, tracing its roots in Bush's earlier work with analog computing machines, and his understanding of the technique of associative memory. It argues that Memex was the product of a particular engineering culture, and that the machines that preceded Memex---the Differential Analyzer and the Selector in particular---helped engender this culture, and the discourse of analogue computing itself.