This site is made by calculator-collectors for collectors. There is information about almost every calculator and shows more than 23750 patents. The site is not complete, every interested collector may join the team (they need also translators).

Picasawebalbum John D. Huey. Here you can see almost every addiator (troncet).

A celebration of old calculators showing the evolution from mechanical calculator to pocket electronic calculator.

Here you can find an on-line version of the Ernst Martin-book and a lot of beautiful pictures.

This Circle is an informal group of collectors.

A site of Andries de Man with original documents on the history of calculators.

A French site from Valery Monnier about all of the 19th century

A site with a lot of information about the stories of mechanical calculators. Particularly there is the virtual BLM's 2008 Brunsviga Expo

A very extensive calculator-collection with many pictures. This site is made by W.G. Bluemich, Bonn, Germany.

Collection of Nico Baaijens, a Dutch collector.

The site of an other collector from The Netherlands.

Collection of Jantine Bloemhof, a Dutch collector. The collection consists of (electro)mechanical calculators to demonstrate to pupils in primary education the different ways of doing calculations before the advent of electronic calculators

A beautiful collection of Eduardo Guillem (Spain). Calculators and typewriters in museum-quality.

Site of the Dutch collector Wim Hasselo. Many pictures and the history of brands as Burroughs and Astra.

A German site with the history of Addiator and other German slide-adders like Addimult, Produx etc.This site is made by Friedrich Diestelkamp.

Here you can find links to other Curta Calculator pages.

This site tells us about the history of the Facit-company.

Site of Martin Reese and Herbert Schneemann.

The website of Kevin Odhner tells us about the Odhner history and shows us many very old pinwheelmachines from the Odhner-company.

A French site about the old calculator Arithmometer from Thomas de Colmar. They show you almost all machines surviving the time.

The site of a beautiful museum especially made for mechanical calculators in Bonn (Germany). Every collector must visit this museum.

Site of the university of Greifswald (Germany). They have a extensive collection of mechanical calculators.

German website of the collection of the Hochschule in Ludwigsburg (Germany).

Mechanical Calculating Machines Discussion List. Here you can join the mailinglist and take a look in the archives.

A forum for calculatorcollectors. You can read all mails and you can be member of the forum