Essay Review : From Avocation to Job: The Changing Nature of Scientific Practice: David Knight, The Nature of Science. The History of Science in Western Culture since 1600 (London: Andre Deutsch, 1976), 215pp., 4.95. ISBN 0-223-96814-8. Robert Charles Post, Physics, Patents and Politics. A Biography of Charles Grafton Page (New York: Science History Publications, 1976), 227pp., $15.95. ISBN 0-88202-046-3. Colin A. Russell, with Noel G. Coley and Gerrylynn K. Roberts, Chemists by Pro fession. The Origins and Rise of the Royal Institute of Chemistry (Milton Keynes, Bucks.: The Open University Press, 1977), x+342pp., 9.50. ISBN 0-335-00041-X. Morris Berman, Social Change and Scientific Organization. The Royal Institution, 1799-1844 (London: Heinemann, 1978), xxv+224pp., 11.00. ISBN 0-435-54060-2. Daniel J. Kevles, The Physicists. The History of a Scientific Community in Modern America (New York: Alfred A. Knopf, 1978), xi + 489pp., $15.95. ISBN 0-394-46631-4