A treatise on proportion in the tradition of Thomas Bradwardine: the \textit{De proportionibus libri duo} (1528) of Jean Fernel (Q391333)

In 1528 Jean Fernel edited the book \textit{De proportionibus libri duo}. Some chapters deal with denomination of a ratio, with fractions and with irrational ratios (in the diction of the author), thus predominantly with quotients of integers. In the article at hand, Sabine Rommeaux translates parts of the book from Latin into English. Additionally she analyses which sources Fernel might have used. Particularly she compares Fernel's work with the book of Thomas Bradwardine entitled \textit{Tractatus de proportionibus seu de proportionibus velocitatum in motibus}, which was written at the beginning of the fourteenth century.