Technology and the Process of Scientific Discovery: The Case of Cosmic Rays

Abstract

Technology and the Process of Scientific Discovery: The Case of Cosmic Rays CHARLES A. ZIEGLER In 1909 ballooning, a technology that had remained virtually unchanged since the 1780s, began to play the role of midwife in the birth of a new branch of science, cosmic-ray physics. This role has not been fully explicated in histories of either scientific ballooning or early cosmic-ray research.1 In describing the nexus between ballooning and cosmic rays, histories of ballooning focus narrowly on the way certain advances in balloon technology were induced by the need to obtain high-altitude cosmic-ray data, while historical accounts of cosmic-ray research treat the balloon simply as an enabling device that was exploited by scientists. It is, of course, well established that techno­ logical innovations are sometimes called forth by the demands of scientific research, and that the technological infrastructure is an enabling factor in the conduct of such research.2 Nevertheless, Dr. Ziegler is lecturer in social anthropology at Brandeis University. Material for this article was drawn from a 1986 study while the author was a Guggenheim Fellow at the National Air and Space Museum, Smithsonian Institution. Portions appeared in Research Report 1986, an NASM internal publication. 'Representative histories of scientific ballooning in the 20th century are: G. Pfotzer, “History of the Use of Balloons in Scientific Experiments,” Space Science Review 13 (1972): 199-242; T. Crouch, The Eagle Aloft (Washington, D.C., 1983), chaps. 19, 20; E. J. Kirschner, Aerospace Balloons (Fallbrook, Calif., 1985). Summaries of early cosmicray research can be found in many textbooks and articles, but there are few substantive historical accounts. These include: V. F. Hess, The Electrical Conductivity ofthe Atmosphere and Its Causes (New York, 1928); R. A. Millikan, Electrons (+ and —), Protons, Photons, Neutrons and Cosmic Rays (Chicago, 1935); V. F. Hess, “The Discovery of Cosmic Radiation,” Thought: Fordham University Quarterly 25 (1940): 225-36; W. F. Swann, “The History of Cosmic Rays,” AmericanJournal ofPhysics 29 (1961): 811-19; B. Rossi, Cosmic Rays (New York, 1964); Y. Sekido and H. Elliot, eds., Early History of Cosmic Ray Studies (Dordrecht, 1984); Q. Xu and L. M. Brown, “The Early History of Cosmic Ray Research,” AmericanJournal ofPhysics 55 (1987): 23-33. The dependence of experiment on technology in pre-20th-century science is well documented; e.g., the study ofgases by Toricelli and Boyle was facilitated by innovations in pump design. See R. Forbes and E. Dijksterhuis, History of Science and Technology (Baltimore, 1963). And astronomical investigations were enabled by advances in the technologies related to instrument making. See D. Dewhirst, “Observations and Instru-© 1989 by the Society for the History of Technology. All rights reserved. 0040-165X789/3004-0002$01.00 939 940 Charles A. Ziegler histories that describe the relationship between ballooning and cosmic rays solely in terms of these perspectives yield an incomplete picture. What is ignored in these accounts is the influence of balloon technol­ ogy on cosmic-ray instrumentation and the consequences of this influence on the complex pattern of findings that constituted the “discovery” of cosmic rays. This article focuses on the interactive relationship that existed from 1909 to 1932 between balloon technology, on the one hand, and the instruments used to measure cosmic rays, on the other. The relation­ ship was interactive in the sense that advances in measuring instru­ ments occurred largely in response to the need to adapt them to balloon use, and advances in balloon technology were made either to compensate for the limitations of the instruments or to exploit their capabilities. Over the long term, the relationship between ballooning and cosmic-ray instrumentation resulted in major innovations in balloon technology and significant improvements in instrumentation. But the short-term outcome of the relationship was less positive because data from the first balloon ascents—initially accepted as valid—were later found to be grossly inaccurate owing to the inability of the instru­ ments to withstand the rigors of flight. After this became generally known, scientists questioned the validity of the measurements ob­ tained on subsequent flights. Doubts about the reliability of such data were only slowly dispelled by improved instruments and advances in balloon technology. Thus, the pace of the interactive...