Science became central to defining the meaning of print in the nineteenth and early twentieth centuries. Since the 1960s, interest in the making of science and technology in the Victorian and Edwardian eras has burgeoned. This chapter focuses on the sciences, with some attention to the very different circumstances prevailing in mathematical and technological publishing. It concerns the periodical, which during the nineteenth century emerged as the form characteristically associated with both specialist publication and accessible science journalism. The chapter discusses the reflective surveys, reference works and introductory manuals intended to entice beginners and educate students. Middle-class publishers and radical agitators alike tended to value science for its propaganda value, using established knowledge to demonstrate the rights or wrongs of the existing order of society. The technological demands of science, technology and mathematics made significant areas for innovation in the printing industry; conversely, the very idea of being a scientist involved skills in negotiating the complex world of printing and publishing.