This is the first of a projected series of thematic volumes derived from the Oxford Companion to the History of Modern Science, published in 2003. This Guide offers a selection of articles from the Companion (plus a few new, mostly biographical, entries) that focus on physics, astronomy and related sciences such as meteorology, geography and geology.

Closely patterned on the Companion in its structure, the Guide lists entries alphabetically and reprints its thematic listing of entries, though unfortunately not the ‘history of science’ entry that discusses the motives for adopting this classification. As a result of the carryover, the comments voiced by reviewers of the Companion largely apply to this volume (see Aileen Fyfe's review in the BJHS 38 (2005), 351–3). Consulting the thematic listing of entries, I was divided between awareness of, and awe before, the inherent impossibility of doing full justice to particular vast areas, and petty quibbling with the choice and ordering of entries. How, for instance, did ‘patronage’ end up being represented by one single entry, ‘brain drains and paperclip operations’? Though the size and format of the entries can lead to false expectations of encyclopedic coverage, searching for information on specific topics proved here also less satisfying than browsing through the volume and hopping from entry to entry. While often the terms I searched were missing or dealt with under another heading, chance encounters made for instructive and inspiring reading. Looking up ‘astronomy, non-optical’, for instance, sends the reader to the intriguing joint biography of Stephen Hawking and Carl Sagan, moving on from there to ‘cosmology’ and ‘pulsars’. The more demanding readership in search of specific information will thus probably be better off consulting, say, John Lankford's History of Astronomy: An Encyclopedia (New York, 1997) or the Dictionary of Scientific Biography. For students and ‘readers of popular science books such as Galileo's Daughter’ (one target readership for the book, according to the OUP website), the volume will no doubt provide an engaging and informative introduction to the history of the physical and astronomical sciences.

What is the value of this excerpt compared to its parent? Apart from its commensurately handier size and friendlier price, the principal novelty and attraction of this volume is its thematic coverage. The decision to feature physics, astronomy, astrophysics, earth science and related pursuits together is unusual enough to be noteworthy. Even though relatively little mileage is made of it in the texts themselves, the very juxtaposition of entries from these different fields and their occasional cross-referencing encourage productive association and comparison. For example, readers interested in ‘Gauss, Carl Friedrich’ are able not only to learn more about his mathematical work by turning to ‘error and the personal equation’, but also to situate him in the contexts of ‘cartography’, ‘geodesy’ and ‘geomagnetism’. The broad chronological coverage further encourages reflection on the ongoing evolution in the relation between the different disciplines and fields, as from Humboldtian science to earth science or between instrument-making and space science. The treatment in a single volume of concepts, actors, institutions and instruments belonging to fields usually considered separately is truly illuminating and could have been put forward in a more explicit way. But this should perhaps be taken as a sign of the limitations of the current historiography and as an encouragement to open up the frontiers of disciplinary histories.