THE READ about the first digital computer was incorrect (CT, July 23, p.12). First, Charles Babbage would have found it difficult to be involved in the construction of any World War II computing devices since he died in 1871. His computing fame resides in his attempts to create a mechanical computer in the mid-19th century.

Second, the writer appears to have conflated the transistor and valve into a single device in referring to "old-fashioned transistor valves". Valves were the fragile and relatively unreliable vacuum tubes, invented in 1906.

Transistors are solid-state, small, robust and reliable -- a totally separate type of device that happens to perform similar functions to those of the valve -- and were invented in 1948. The leap from transistors to integrated circuits was smaller than that from valves to transistors.

© 1997 - Stephen Dawson