Site Information
The Rarities Gallery is images of rare items from the collections of slide rule and calculator enthusiasts around the world.
Its purpose is to share rare item images and information with fellow enthusiasts.
The Gallery is in its infancy; it will grow continuously as items are added.

To view the site
Click HERE or Click Complete gallery in menu above.

To use the site
1. Browse. Scroll through the thumbnail images. To view details, click thumbnails.
2. Search. Click Search in menu above and enter your information in the form.      

Contributing to the site
Please contact . We will be happy to work with you to add your rare items to the Rarities Gallery.

Commenting or asking questions
Please send email to

Determining rarity
In conjunction with our 'donors' we assign a rarity rating to each item, based on the system devised by Herman van Herwijnen
(1929 - 2004), renowned Dutch collector, author, and creator of Herman's Archive, a collection of 5,000 slide rule images on CD.
• RR = Rare - 1 of 25 collectors has one; it may take a year to find an example in the marketplace.
• RRR = Very Rare - only a few known to collectors; may be several years before it comes up for sale.
• RRRR = Extremely Rare - a museum piece; unlikely that an example will come up for sale.

Created by Oughtred Society members Ted Hume, Rod Lovett, and Richard Davis.