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History of Technology

brothers. They were paper manufacturers in Annonay, forty miles south of Lyon. Advances in the study of gases made lighter-than-air machines theoretically feasible; the brothers provided the inspiration and the expertise. Their story indicates the vigour of French provincial science and technology while it illustrates the difficulties of dealing with an arthritic bureaucracy entangled in an archaic class system. Gillispie, rightly, ignores the intrepid birdmen who, at various times, had tried to fly by using artificial wings and jumping from high places, usually disastrously, invariably without benefit to their successors. The pioneers hoped that balloon travel would become commercially viable one more was learned about upper wind systems. But they were landsmen and the analogy with sailing ships was false. Here, Gillispie is too charitable. Meusnier's plan for a giant airship, manually driven by three huge propellers, would have been scorned by contemporary sailormen. Unfortunately this fascinating account ends with the Revolution and provides no answer to Samuel Johnson's criticisms (1784). The balloon cannot be directed at will and has added nothing to our knowledge of the atmosphere for mountaineers have climbed higher than balloons have ascended. Johnson concluded, prosaically, 'I had rather now find a medicine that can ease an asthma'. However, J. L. Pritchard points out that young George Cayley was probably deeply impressed by early balloon flights and Cayley's influence extended down to the Wright brothers. On the other hand, Maurice Crosland has called attention to Gay-Lussac and Biot's 'scientific expeditions in a balloon' of 1804. The scientific results of Gay-Lussac's extraordinarily courageous ascent to over 7,000 metres had some significance for the infant atomic theory. But these and other developments are not mentioned in the last quarter of the book which is concerned with various, non-aeronautical, inventions and ideas of Joseph Montgolfier and his greatnephew Marc Seguin. This reader disagrees with Gillispie on a few minor points, and there are one or two mistakes. For example, errors in the formulae on pages 89-90 make them dimensionally inhomogeneous. And Meusnier did not, as implied on page 107, invent the concept of the metacentre (that was due to Bouguer). But these are slight blemishes on what is a very well written, well produced and excellently illustrated book.