Mechanical calculators

My name is Kees Nagtegaal. I made this site for collectors of non-electric mechanical calculating devices.

My collection exists of over a two hundred:

• Addiators and other slide-adders (Addiator, Produx , Addimult and many others.)
• Some pinwheels (Odhner, Brunsviga)

You can see all of those with description in the gallery. Feel free to check out my books and manuals, too.

If you have any nice object (and a nice price) for my collection, please contact me. I am very interested in addiators and other slide-adders.

If you don't have much time, you can watch a movie in which you can see my entire collection of addiators in 2 minutes.

If you are interested in Addiators: there is a catalogue "Addiators and other slide adders" and a "advertisements book""

If you want to see or download or print this catalogue or that book you had to go to the page  Addiator Catalogue  or Advertisings book or click at one of the pictures.