Wood Cased Comptometer, Serial 5668
Item History & Price
| Reference Number: Avaluer:6839470 | Maker: Felt & Tarrant |
The Comptometer’s place in history is significant: introduced in 1887, it was the first key-driven mechanical calculator that was commercially successful, and it worked so well that it was in continuous production – with many improvements along the way – until the mid-1970s. Between 1887 and 1903, all Comptometers were built in wood cases; steel cases were used after that. There were approximately 6500 wood-case Comptometers built. With its serial number of 5668..., this one is in the last 15% made.
This Comptometer is in fair condition with the biggest and most obvious defect being that the 8th column of keys is entirely missing. Surprisingly, that seems to have no effect on the other columns, and carry even works from the 7th to the 8th column! The mechanism on this one definitely needs a clean and lube. Many of the keys don’t travel their full distance and add lower numbers than they should. Some keys are sticky and slow to return…some need to be pulled back up. There’s a spring-loaded snap when it goes from 9 to zero, and the snap is powerful enough to make some of the wheels overshoot and show 1, 2, or 3, after being “cleared”. Being an early Comptometer, this one adds on the downstroke of the keys, not the on the upstroke as on all later models.
This Comptometer is from the collection of Robert K. (“Bob”) Otnes, PhD, one of the founding members of the Oughtred Society and the original editor of the Journal of the Oughtred Society. It is being sold by the Oughtred Society on his behalf.
The Oughtred Society was founded in 1991 by a group of slide rule collectors and is dedicated to the preservation and history of slide rules and other calculating instruments. Membership is open to anyone. Further information about the Oughtred Society can be found at: http://www.oughtred.org/.
PayPal is the only accepted form of payment. Buyers within California will be charged 7.25% sales tax.
Shipping will be by USPS Priority Mail. Shipping charges will be somewhat higher for destinations outside the USA.
This Comptometer is in fair condition with the biggest and most obvious defect being that the 8th column of keys is entirely missing. Surprisingly, that seems to have no effect on the other columns, and carry even works from the 7th to the 8th column! The mechanism on this one definitely needs a clean and lube. Many of the keys don’t travel their full distance and add lower numbers than they should. Some keys are sticky and slow to return…some need to be pulled back up. There’s a spring-loaded snap when it goes from 9 to zero, and the snap is powerful enough to make some of the wheels overshoot and show 1, 2, or 3, after being “cleared”. Being an early Comptometer, this one adds on the downstroke of the keys, not the on the upstroke as on all later models.
This Comptometer is from the collection of Robert K. (“Bob”) Otnes, PhD, one of the founding members of the Oughtred Society and the original editor of the Journal of the Oughtred Society. It is being sold by the Oughtred Society on his behalf.
The Oughtred Society was founded in 1991 by a group of slide rule collectors and is dedicated to the preservation and history of slide rules and other calculating instruments. Membership is open to anyone. Further information about the Oughtred Society can be found at: http://www.oughtred.org/.
PayPal is the only accepted form of payment. Buyers within California will be charged 7.25% sales tax.
Shipping will be by USPS Priority Mail. Shipping charges will be somewhat higher for destinations outside the USA.
