This study applies a rhetorical and a sociolinguistic register analysis to a corpus of articles from the 'Philosophical Transactions' of the Royal Society of London and interprets the integrated results in relation to their socio-historical context. It is shown that early research writing was strongly influenced by communicative norms of genteel conduct; that greater attention to methodology and precision in the interest of scientific specialization caused important textual changes in the 19th century; and that nowadays extensive theoretical discussions replace experiments and methods as rhetorical text bodies.