Tools for an ideas trade

Scientific instruments, the subject of this fine book, are always on the minds of professional scientists, mainly because they have governed the rate at which science advances. Often the instrument is regarded as the key component that segregates experimentalist from theorist and, arguably, the proper scientist from the one dealing in conjectural abstractions. But maybe this is not fair. It is a rare theorist who does not lean heavily on boxes full of humming computers, and these are scientific instruments par excellence .

Active research scientists are always dissatisfied with their instruments. The continual quest for betterment means that obsolete instruments are plentiful. Dusty cupboards in research laboratories, universities and schools bulge with discarded examples, many displaying the ravages of time and practical application. These are stored not only because the scrap heap is no fitting repository for a long-standing and trusty helpmate, but also because of a nagging feeling that the bits might come in useful.

The academic study of the history of scientific instruments is a relatively recent phenomenon. Science historians used to be only too happy concentrating on the concepts and philosophy of their subject, despite being aware that many of the step-functions punctuating scientific progress were produced by instrumental novelties as opposed to ideas.

Take optics as an example. Polished metal reflecting mirrors were known in classical times, and crude spectacles were used in the middle ages, but further advances in optics were held back by the poor quality of manufactured glass. By the 1600s, however, industrialists started to make glass that was reasonably transparent. It was then but a short step to the combination of two lenses to produce instruments such as telescopes and microscopes. At a stroke people were introduced to both the very small and the very distant. Soon the popular imagination was fed by intricate details of the anatomy of the flea and the stellar nature of the Milky Way.

Since those times, the pace of improvement of scientific instrumentation has been hectic, and we witness, for example, the field ion microscope producing images of individual large atoms and a huge optical space-telescope detecting galaxies that are so faint that they are close to the edge of the universe.

Scientific instruments started to be produced in significant numbers from the 17th century. There was a symbiosis between the scientific and industrial revolutions. The former demanded more complicated and accurate instruments for research purposes. This led to an accumulation of industrial craft skills and the ability to mass-produce not only instruments for everyday use but also for a multiplicity of industrial applications.

Today the popularity of old instruments among both private antique collectors and specialist museum curators has never been greater. Their special appeal relies more on functionality than mere aestheticism. Deeper than the decorative aspect of the instrument is its worthiness, sense of purpose and inherent usefulness.

In comparison to many museum artefacts, the scientific instrument looks as though considerable thought has been applied to its design. All those knobs, dials, buttons, scales, eyepieces, switches, pen-recording charts and winding handles have not been scattered around at random. They are where they are for specific reasons such as ease of use and handiness. The fact that the sole purpose of the instrument is to produce accurate, dependable results, which are reproducible over a long time, means that the craftsmanship and the materials are of the highest standards.

Instruments also have considerable intellectual appeal, the beholder continually being reminded of the underlying scientific principles. You cannot help looking at a sand glass or a sundial and musing on the physics of granular flow or the variable velocity of earth around its elliptical orbit.

With the growing popularity of instruments comes a search for knowledge and understanding and a desire to read more about them. The scientific instrument bookshelf is rather underpopulated and a worthy addition is to be greatly welcomed.

Robert Bud of the Science Museum, London, and Deborah Jean Warner of the National Museum of American History (Smithsonian Institution) have brought together 3 instrumental entries, from about 220 university and museum contributors, to produce Instruments of Science: An Historical Encyclopedia .

Entries range widely from the ancient to the modern, the industrial to the esoteric and the medical to the meteorological. So the slide rule is the neighbour of the solar neutrino detector and the computer tomography scanner comes just before concrete-testing instruments. The orrery (pictured) is sandwiched between the ophthalmotonometer and the oscilloscope; paper-testing equipment is adjacent to the pantograph and the patch-clamp amplifier, and trios such as tide predictor, torquetum and torsion balance and visceroctome, viscometer and vocational aptitude tests abound.

Each entry is beautifully illustrated and the 1,000-word texts clearly and concisely cover the workings as well as the origins, development and most recent manifestation of each instrument. Given the variety and the disparate natures of the readership, great care has been taken to explain the intricacies of each instrumental technique to the uninitiated. A small bibliographical entry is also provided for each entry.

The entries have been chosen with reference to modern scientific, medical and engineering practice as well as by trawling through museum catalogues and the indexes of historical scientific texts.

The end result is a book that not only tells you what these instruments do and how they work but also knits together the threads of our scientific endeavour, and underlines the fact that the hand, the eye and the measurement are foundation stones of our quest.

David Hughes is reader in astronomy, University of Sheffield.