The present calculating device, invented and patented by the Parisian Casimir-Louis Chambon in 1876, is a four printed cylinder 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. The total of say 6,216 at 4 percent could be figured by adding the sums shown in the four rows.
The apparatus was made of ebonized wood, paper, silvered metal and glass, with measurements: 175 x 100 x 35 mm.
The present example is one the earliest examples engraving “C.L. Chambon inventeur” and printed by “Baster & Vieillemard”. The late examples, offered for sale by Chambon & Bayle compagny, are engraved “Chambon & Baye” and printed by “Girard & fils.”
Maurice d’Ocagne wrote about this calculatin machine :
““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 the example illustrated at the History of Computers : http://history-computer.com/CalculatingTools/Gadgets/Tachylemme.html
Despite a small damage at the paper on the number 600 (see the two last pictures), very fine original condition of this rare and elegant calculating device.
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Established by Alexandre Piffault in 2014 and based in Paris, Le Zograscope specializes in antique and rare books in Science, Medicine and Technology, and rare antique instruments in the same fields. We have especially a strong interest in early and continental microscopy, early and special mathematical/drawing instruments, medical and surgical instrument, and rare technology.