(:title Centigraph Adder, 1891, serial no. 1523:)

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This is an extremely rare example of a Centigraph (it is believed to be one of 4 known to exist worldwide[^The known surviving Centigraphs are: \\(i) Sold by Southebys 7 October 1994. Estimated price  € 6,000-8,000; \\(ii) Sold by Brekker 24 Nov 2007.  Estimated price : € 3,000/5,000 and ultimately sold for € 11,067 [Bulletin de Liaison de l’Association Nationale des Collectionneurs de Machines à Ecrire et à Calculer Mécaniques, 30 Mars 2008, p 11.] \\(iii) Held in the Collection of Historical Scientific Instruments, Harvard University.   1453: Serial Number  [[http://dssmhi1.fas.harvard.edu/emuseumdev/code/emuseum.asp?emu_action=searchrequest&newsearch=1&moduleid=1&profile=objects&currentrecord=1&searchdesc=centigraph&style=single&rawsearch=id/,/is/,/3701/,/false/,/true|Harvard emuseum website]] and \\(iv) this one Serial 1523: Provenance - Purchased from the Dunottar Collection in May 2014, who in turn had purchased it from Tom Grossman - Rochester Hills, MI, USA, in 19 Dec 2008.^]) and invented by Arthur E. Shattuck and patented in 1891.  It is a mechanical adding machine innovatively utilised a keyboard to transmit rotational motion to a central accumulating rotating gear wheel. It was sold by the American Adding Machine Co.

The machine is driven by a spring which is wound up by winding the main wheel.  Numbers are accumulated by pressing one of the five number keys.  Where a number greater than five is to be input, two keys may be pressed simultaneously.  The result is displayed in the numerals displayed on the front most disc. The counter can count up to 99.  Beyond that, the arrow on the left of the rotating disc can point to a number from 1 to 5. These delineate the hundreds accumulated. Thus the adding machine can count up to 599. Beyond that, the adding machine must be reset. This is achieved by putting the arrow back to its outermost position and then resetting the counter.

Provenance: ex “Dunottar Collection” of the late David Gamble, 2014.

!!!Patent
The US Patent for the Centigraph was taken out by Arthur E. Shattuck as inventor on 9 June 1891 - see [[ http://meta-studies.net/pmwiki/uploads/CentigraphPatent.pdf|US Patent 453778]].

!!!Article in '/La Nature/' 1893
The [[LaNature1893|1893 issue of '/La Nature/']] contains an article "Machines A Additioner" by G. Mareschal describing the working of the Centigraph together with a more standard stylus operated ribbon adder.[^G. Mareschal, "Machines A Addtioner", '/La Nature/', 1893, pp. 539-540.

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