The book studies John Tyndall, a Victorian physicist, but it is not a biography. Rather, DeYoung’s goal is to "demonstrate Tyndall’s enormous impact on the Victorian concept of science and on the public image of the scientist as a figure of authority in British society" (1), an impact that DeYoung argues has been previously neglected, both by the Victorians themselves and by contemporary critics. The biographical details are only sketched in through intermittent dribs and drabs and only as they are relevant to Tyndall's approach to science.

Tyndall came to prominence at the transition between amateur and professional science, a transition that DeYoung acknowledges was not smooth or immediate (11), and he spent much of his career advocating for the alteration of the role of the sciences in culture. The main strength of A Vision of Modern Science lies in the way that DeYoung connects Tyndall's ideas to the larger debates happening in Victorian culture at the time. This is great, because one thing I've really struggled with in my research on Victorian science so far is good overview of how the processes of science as a whole were viewed-- you can find what people thought about biology, or geology, or physiognomy, but what did people think of "science"?  DeYoung answers that question.

Tyndall was one of the key participants in the debate over the roles of theology and science in society. Tyndall himself was antagonistic to organized religion, especially Catholicism: he believed wholeheartedly in religion's use for an inner emotional life, but he did not believe that theology should guide public decisions, nor that it could purport to deliver truths about the observable world. DeYoung points out that the debate was not so one-sided as "religion vs. science"; there were many different components. There were debates over how effective prayer was, debates over whether or not science could claim to deliver truth, debates over whether or not theology could count as a science, and debates over what was the role of science in society. Tyndall had a position on all of these issues, and in relating his position, DeYoung explicates the controversies in general. She uses a lot of primary source documents-- lectures, pamphlets, periodical publications, cartoons, and more-- and in doing so, allows the reader to obtain a quick understanding of what was at stake in any one of these multiple debates.

Particularly instructive is her discussion of the 1874 Belfast Address, where Tyndall (in his role as president of the British Association for the Advancement of Science) argued that only science could exert authority over the organic world. Tyndall was reacted against quite negatively, but DeYoung shows that many of his critics misunderstood his position; Tyndall was not one of the "scientific materialists," who believed that science could answer all questions, but rather a "transcendental materialist," who agreed that science could not follow the chain completely from molecules to consciousness; it still had its limits. In making his address, Tyndall was seen as exceeding the bounds of the authority of the scientist, which as DeYoung points out, indicates that bounds for the scientist had indeed been set, where they had not earlier in Tyndall's career.

In marking the changing reactions to the Belfast Address over time, DeYoung traces how societal attitudes also changed; eventually the debate was about not whether it was appropriate for a scientist to make public commentary, but what was the appropriate venue for doing so. DeYoung's final chapter, which examines the positions of three post-Tyndall scientist, is particularly useful in revealing societal attitudes and controversies about science, as it demonstrates how Tyndall gradually became irrelevant: some of his positions had been adopted by society at large, so his advocacy was unimportant (such as the presence of science degrees at universities), while others were lost completely (scientists as social commentators), and others were simply not meaningful anymore (popularization of science became more difficult as the disciplines became more specialized). By the end of Tyndall's career, university laboratories had gone from being a dream to being a reality. In examining Tyndall specifically, DeYoung explicates a wide variety of perspectives on science and the scientist that can prove a boon to any scholar of the history of science or of the Victorian period.

The book does have some shortcomings, though. It analyzes Tyndall's ideas fairly thoroughly, but sometimes the thoroughness is redundant; for example, "The Aims and Benefits of a Scientific Education" is not very distinct from "Scientific Method as the Foundation of Education." On the other hand, despite Tyndall's ideas feeling overexplained, it's sometimes hard to obtain a grasp on what some of them actually were. In her discussion of the influence of Carlyle on Tyndall, and in many other sections, DeYoung explains that Tyndall and his scientist cabal, the X Club (what an awesome name!), wanted scientists to take on an important role within society, but DeYoung never adequately explains what that important role would be, beyond the fact that Tyndall once grew frustrated when a committee he sat on refused to adopt his plan for the generation of light in lighthouses.  I am sure there was more to it than that!

In the book's conclusion, DeYoung briefly mentions the attempt of Tyndall and the X Club to intervene in the "Irish Question" (213), but it comes too late, and even here it is not clear how Tyndall's position was (ostensibly) derived from the scientific method. It may be that DeYoung cannot articulate exactly what the scientist's role in society was to be because Tyndall himself never fully did, but in that case I would have liked to have seen that failure explored. Similarly, the education chapter repeatedly states that Tyndall saw the scientific method as the beginning of all education, but supplies no examples of what this would mean in practice.

In the book's final chapter and conclusion, DeYoung emphasizes the fact that Tyndall was perceived more as a popularizer of science than as a practitioner, and argues that this is unfair. But it is a crime that A Vision of Modern Science is itself guilty of; the section on Tyndall's own discoveries (in areas as diverse as heat physics, glaciology, and bacteriology) is one of the least interesting parts of the book. But if Tyndall had only made a series of interesting discoveries, then Ursula DeYoung would not have undertaken to write a book about him. John Tyndall's foremost contribution to science came in his philosophy, his popularization, and his participation in the Victorian debates on science, and through these activities, DeYoung is able to explore much about Victorian science as a whole. His scientific contributions, though undoubtedly important, take a necessary backseat to this longer-lasting and more influential work, and rightly so.