It is telling that two of the most useful background sources for this period, George H. Daniels' 1967 essay, “The Process of Professionalization in American Science,” and Robert V. Bruce's Pulitzer Prize winning book, The Launching of Modern American Science: 1846–1876, should both have titles with words of becoming, for this was indeed a dynamic period. As Daniels puts it, “Most of the controversies within science can be understood in terms of tensions inherent in the transition from one mode of scientific activity to another” (p. 151); and Bruce notes more specifically, “By 1846 the influence of technology was proving to be a match for that of abundant land, and by 1876 the way of collective, organized enterprise clearly dominated American life. The tension between these two ways to wealth were mirrored in American science during the nineteenth century, and not by coincidence” (p. 5). The scientists of this period seemed aware that they were both the raw material and the potential victors (in bounty and fame) of these dynamic years, which may account in part for the urgency, competition, and tension that marked it. If there is one word that connects all the various themes of this period, it is tension, and so it is around these tensions that I focus this introduction to Part Two.

Lazzaroni / U.S. Coast Survey / Dudley Observatory / National Academy of Sciences

If Louis Agassiz could be considered the face of American science in the antebellum period and Joseph Henry the brains, then Alexander Dallas Bache would be its body.