RECENTLY closed in the Museum to make way for the 1998 Student Exhibition was a temporary exhibition initiated by one of last-year’s M. Sc. students, Paola Bertucci. The exhibition was entitled ‘Fire and Art’ and took as its subject eighteenth-century electrical practice.
In the eighteenth century electricity was a major preoccupation of natural philosophers and the lay public alike. Electrical instruments lived a ‘double life’ between the closed space of the laboratory and more public spaces such as coffee houses and theatres. The production of sparks and the attraction and repulsion between charged bodies could be exploited in amusing experiments and became a fashionable form of entertainment for polite society.
The exhibition was structured around two main cases which represented the two most pervasive themes around which eighteenth-century electrical practice organized itself: on the one hand the drama and entertainment offered by the display of electric ‘fire’ and on the other the more useful application of electricity to the ‘art’ of healing. Both themes offered contemporary proponents of electricity excellent opportunities for advertising and promoting electrical research and for demonstrating its power and virtues before the public.
Electric fire, dramatic in itself, could be deployed in many entertaining ways, through the use of simple electrical ‘toys’ of various sorts. ‘Fulminating boards’, in which a series of sparks jumps between small gaps in a conducting track to reveal the pattern of a hidden word, were a straightforward way of manifesting the fire, while electric swings and electric dancers could be driven by the attractive and repulsive forces of static electricity, and electric pistols and cannons ignited by the heat of an electric spark.
As a medical remedy, electricity was somewhat controversially deployed in the cure of various diseases, ranging from common toothache to palsy, dropsy, tetanus and gout. It was put forward especially as a rather less painful therapy than many of the crude surgical treatments then common. ‘Medical electricity’ was promoted by natural philosophers and instrument makers, as well as by surgeons, apothecaries, and self-trained practitioners, with instruments used in other aspects of experimental practice being modified and adapted to medical purposes. All approaches to the medical applications of electricity, however different, shared a common rhetoric of the usefulness of electricity as a complement to its entertaining aspects.
The electrical machine was the essential element for all electrical experiments in the period. According to the main theory of the time, the action of rubbing a piece of glass (a globe, a cylinder or a plate) against an insulator (commonly a leather cushion) ‘sucked’ electric fluid from the earth and gathered it on the surface of the glass. From there it could be collected by metal spikes and directed onwards via a ‘prime conductor’ – usually a long hollow brass tube.
Impressively large machines, such as the double-plate machine in the basement of the Museum, were built for wealthy patrons throughout Europe while smaller apparatus satisfied the improvised needs of itinerant electrical experimenters. Portable and cheap machines found a place in the market for self-treatment so popular in the eighteenth century Included in the exhibition was a small globe machine by George Adams, as well as a portable machine designed by the Knightsbridge instrument maker and medico-electrical practitioner John Read.
Other items on display included ‘medical directors’ for conveying electrical fluid to and from the patient’s body, Leyden jars and medical jars for storing the electric fluid, and several ‘thunder houses’ – collapsible models of houses with rounded and pointed conductors for demonstrating the effects of lightning on buildings.
The frontispiece of George Adams’ An Essay on Electricity (London, 1785) was chosen as the backdrop to the central showcase. Illustrated above, it shows the administration of electricity, generated with a cylinder electrical machine and communicated via a cylindrical prime conductor, to the forearm of a young girl through medical directors. Examples of the components of the apparatus in the frontispiece were all available in the Museum: it was therefore possible to create a life-sized version of Adams’ scene in the showcase, the operator and his young patient excepted.
From a personal point of view, the work on the exhibition, after the M. Sc. course, provided a valuable opportunity to grasp and exploit the potential of instruments as historical resources, giving a real, and ‘experimental’, support to historical and historiographical lessons already learnt.