The Deaths of the Slide Rule
Journal of the Oughtred Society, Vol. 23, No. 2 (Fall 2014), 6-17
12 Pages Posted: 11 Oct 2014 Last revised: 24 Jan 2018
Date Written: September 1, 2014
It is generally recalled or believed that the slide rule was the preeminent means of calculation until it was swiftly displaced by the electronic calculator, notably by the Hewlett-Packard HP-35 in 1972. But sales of major brand slide rules were declining in the sixties and early seventies, and in a number of specialty applications and emerging economies, the devices continued to find utility and demand through the eighties. Thus there was not a single "death of the slide rule": instead, it met a cascading demise, quickly losing the general-application users in affluent markets but more slowly dropping specialty and developing-country segments. This survey of the literature and evaluation of the business commentary on product obsolescence provide a more complete description of how a once dominant technology was confined to diverse but increasingly isolated uses before meeting its end.
Keywords: slide rule, death of the slide rule, calculator, calculation, product obsolescence, diffusion of innovation
JEL Classification: L63, L86, O3
Suggested Citation: Suggested Citation