During the 1840s and the 1850s botanist Joseph Hooker developed distinct notions about the proper characteristics of a professional man of science. While he never articulated these ideas publicly as a coherent agenda, he did share his opinions openly in letters to family and colleagues; this private communication gives essential insight into his and his X-Club colleagues' public activities. The core aspiration of Hooker's professionalization was to consolidate men of science into a dutiful and centralized community dedicated to national well-being. (...) The nation in turn owed the scientific community for its ministration. When the government bestowed funds and status on men of science it was rewarding science -- not purchasing it. His proposed reforms were piecemeal, immediate, and above all practical. He harbored no taste for vast millenarian transformation, and rested his conception of scientific professionalism upon a respectable High Victorian foundation of patronage and pillars of duty, reciprocity, intimacy, and inequality. The process of professionalization he envisioned was as much shrewd compromise between existing interests as a vindication of principle. His power and prestige from the mid-1850s onward gave him considerable ability to carry out his reform program, although his general success did occasion some undesired consequences for the status of natural-history pursuits. (shrink)