01 June 1999

Escaping from the footnotes of history

It is always pleasant to meet kindred spirits, and Babbage recalls his introduction in 1840 to fellow Devonian Mr Thomas Fowler. A bank manager from Torrington, Fowler was visiting London to demonstrate his wooden calculating engine. Babbage thought that the device, of sliding-rod construction and using the ternary number system, showed remarkable promise. Its inventor, alas, died three years later, leaving it in pieces. Soured by the experience of competitors copying his Thermosiphon central heating system, Mr Fowler left no drawings for the calculator’s reconstruction. The only record is a commemorative window in St Michael’s Church, Torrington.

Unfortunately this is all too common a story. In our electronic age, mechanical computers seem destined to be mere quaint footnotes to history. In reality, their significance was considerable. Notably, the Turing ‘Bombe’, crucial to Britain's decoding of German Enigma messages in World War II, was a programmable mechanical computer, albeit not “absolutely general” machine like the Analytical Engine.

Mr James Redin’s “X-number World of Calculators” at http://www.dotpoint.com/xnumber/vintage.htm celebrates hand-cranked comptometers, slide-adders, and other descendants of early devices such as the Pascaline and Leibniz Stepped Drum calculators. Mechanical calculators were the mainstay of businesses until only a few decades ago. One of the earliest such devices, the abacus, is still in use today.

Recent developments, however, may yet revive mechanical calculation in mainstream science. At the web site of Sandia National Laboratories, USA (http://www.mdl.sandia.gov/micromachine/) Babbage recently learned of some delightful ‘micromachines’ no larger than a pollen grain. Formed as an integral part of a CMOS microchip, these devices include locks, shutters, sensors, encoders, and even a steam engine.

Moving down to atomic scales takes us into the realm of Dr K Eric Drexler’s ‘nanotechnology’. Atomic-scale gears and bearings are theoretically possible, and from these, nanocomputers could be built. Babbage finds most amusing the thought of a nano-sized Analytical Engine driven by a steam motor little larger. A more likely component, however, is the sliding ‘molecular abacus’ reported in the February/March 1999 issue of Scientific Computing World. It seems that Mr Fowler’s sliding-rod concept, albeit on a far different scale from his prototype, could at last find application.

A footnote from Babbage: I was delighted to read in the Western Morning News, August 30th 2000, an item about two reconstructions of Mr Fowler's Engine by Roy Foster, an engineer from Torrington, and Mark Glusker, a product designer from California. The construction was made possible through the work of historian Pamela Vass, also of Torrington, whose research led to the rediscovery of Fowler's notes on his Engine's design, given as a deathbed dictation to his daughter. A short biography of Fowler may be found at www.thomasfowler.org.uk; Mark Glusker's model may be seen at www.mortati.com/glusker/.