A note on the “machine of Roemer” in late-17th century China, Antoine Thomas, S.J., and the first contacts of Ferdinand Verbiest, S.J., with the Jesuits in Paris

This contribution focuses on a detail of Jesuit astronomy (especially eclipse observation) in China, viz. the introduction of new instruments such as the “machine de Roemer”: arguments are offered to prove that its introduction in China is not to be attributed to the “mathématiciens du Roy” (arr. in 1688), as it was apparently known to Ferdinand Verbiest, S.J. (Head of the Astronomical Bureau/Qintianjian) in 1682. When trying to reconstruct the “route” followed by this innovation, again the figure of Antoine Thomas, S.J. (1644-1709) - “assistant” and later first successor of Verbiest at the Astronomical Bureau - comes to the fore, who may have got acquaintance with this innovation through the issue of 1682 of Journal des sçavans, not in Peking, but in Macau. This is a new element, which shows again the important (but silent) part Thomas played in the communication of astronomical novelties, printings etc. from Europe to China, and vice-versa.