[Composite editorial contents in French chemical journals].

This study of a corpus of French chemistry journals between 1800 and 2010 shows the relevance of the journal as the primary mode of communication, confirming the results of the general survey presented in this issue. However, a study of their contents is questioning the apparent unity of this phenomenon: the journal appears as a physical medium consisting in a common container including a wide range of information categories transferred over time to digital platforms in development since the end of the 20(th) century.