Louis-J. Troncet (b. 1850), “Sur un Calculateur mecanique appele Arithmographe“, an article in Comptes rendus, March 30, 1903, volume 136 #13, pp 785-840, the paper occupying pp 807-809, with a nearly full-page image of the calculating machine. This is the entire weekly issue, offered without the outer wrappers, and removed/detached from a larger bound volume. VG copy. $145
It is hard to tell the dimensions of this instrument, but I’m guessing it was perhaps 8″ tall, judging by the stylus attached to the eight of the calculator. Troncet developed a very popular instrument in his “Arithmographe”, which evidently first appeared in the late 1870’s, with versions of the machine manufactured for decades, with millions sold. This device comes relatively late in the series, though it also seems to be the first offering multiplication and division.
[Note: the scan of the device makes it seem as though there is vertical discoloration or an old fold–neither is there. This is just a shadow from not pressing down hard enough on the paper.]