Improved Willis Planimeter, With Instructions, S/N 6061
Item History & Price
| Reference Number: Avaluer:124520 | Maker: James L. Robertson & Sons |
Edward Jones Willis first patented his cross-shaped planimeter in 1894, with further improvements being patented in 1896 and 1901. This one is a later model with all the improvements. The frame that holds the 6-scale ruler and measuring disc is on the right side rather than the left, and the disk itself now has rollers that allow it to ride along a fixed rod, rather than being fixed to the rod and the whole rod moving on rollers.
This Willis is in absolutely ...superb condition, as you can see in the pictures, and includes the original 8-page instruction book, which is a quite fragile, with pages pulled out of the staples, but it is all still there.
This planimeter 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 Willis is in absolutely ...superb condition, as you can see in the pictures, and includes the original 8-page instruction book, which is a quite fragile, with pages pulled out of the staples, but it is all still there.
This planimeter 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.
