ABSTRACT
This chapter argues that historical linguistic change is mediated by register differences at a much more specific level than has been previously recognized. Two specific case studies of 20th-century historical change are presented. The first explores variation among sub-registers of news reportage, comparing the patterns of change in magazine articles from TIME Magazine to those found in newspaper articles from the New York Times. The second case study then explores variation among sub-registers of academic research writing. This study shows how differences associated with academic discipline (science versus social science versus humanities) correspond to systematically different trends in historical change. Even more surprisingly, this study shows that science articles published in two journals aimed at multidisciplinary audiences, the Philosophical Transactions (PT) and Science, differ from science research articles published in journals targeted towards more specialized audiences. This case study shows that linguistic variation among these sub-registers of academic writing apparently reflects differences in the audience and purposes of the two types of journals. Thus, tracking the historical development of PT articles (as is the focus of many historical studies on science writing) provides at best an incomplete perspective on historical change in scientific discourse.
