This study is a linguistic analysis of the first two academic periodicals from their creation in 1665 until the end of the seventeenth century. These were the Journal des Savans in France and the Philosophical Transactions in England. The analysis is carried out within the framework of Systemic Functional Linguistics. The linguistic features and aspects of the theory necessary for understanding the rest of the book are explained, and the historical situation is described in order to place the texts in the context from which they derived. The corpus is made up of a selection of issues for the years 1665, 1675, 1685 and 1694/5, totalling over 66,000 words for the Journal des Savans, and over 77,000 words for the Philosophical Transactions. Thematic structure and progression, types of process, expressions of modality, and nominalised processes are studied in each of the periodicals and the results compared. It is shown that differences in the results for the two journals derive from differing editorial decisions, which themselves are engendered by the historical context.