This calculating device, invented and patented by the Parisian Casimir-Louis Chambon in 1876, is an example of a rotatory cylinder tabular calculating machine. It consists of four printed cylinders of 1 to 9, 10 to 90, 100 to 900 and 1000 to 9000 so arranged that percentages for every half percent from one to six percent can be read through slits. It includes 396 cells. A total of say 6,216 at 4 percent can be figured by adding the sums shown in the four rows. The apparatus is made of ebonized wood, paper, silvered metal and glass, with measurements: 175 x 100 x 35 mm.
This is one the earliest examples showing the engraving “C.L. Chambon inventeur” and printed by “Baster & Vieillemard”. Later examples, offered for sale by Chambon & Bayle company, were engraved “Chambon & Baye” and printed by “Girard & fils.” Maurice d’Ocagne wrote about the Tachylemme : “This arrangement of numerical table on adjacent cylinders has the further advantage of being extendable to certain tables having three entries. It is clear that, if by some means the numbers read from the cylinders can be made to vary according to the values of a third entry, then a triple barème has been achieved. It is this idea that Mr. Chambon most ingeniously put into practice in his Calculateur d’intérêts, which gives the interest payable, for any number of days, on capital sums up to 99,999 Fr. at raies of 3, 3.5, 4, 4.5, 5, 5.5, and 6%. The vertical columns of the table correspond to the first entry, the number of days. As in the Didelin device, the units, tens, . . . ,tens of thousands are assigned to the various cylinders, on each of which an endless loop contains the nine lines corresponding to the second entry.”
See also the example illustrated at the History of Computers : http://history-computer.com/CalculatingTools/Gadgets/Tachylemme.html
This rare and elegant calculating device is in very fine original condition (although there is minor damage to the paper at the number 600).
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