Very rare, I find this one at ebay. The final price will be high I guess… But meanwhile, I get the pics and info for all of us.

This rare find dates from 1796 – 1804, the time when the makers, Dring and Fage occupied the address marked on it of 248 Tooley Street, London Bridge. It is a four sided 12 inch slide rule for use in the brewing industry of a type originally invented by a Custome & Excise officer named Everard in the 17th century. Designed to facilitate all manner of calculations, particularly the alcoholic content in order to ascertain the amount of duty payable, the instrument is marked with a staggering amount of information. Each of the four sliding centre pieces, brass tipped at one end, has a mass of information on the back - I’ve shown a little from two of these. The wood has a beautiful patina and there is only very slight knocks and damage, the most noticeable being a very old chip at one end as shown in the photos. It also has its original hard leather case which is also undamaged but beautifully aged. There is the name of P R Prideaux hand written inside one part of the slide rule. This is quite a remarkable item, stunning on display and very rare indeed.

A nice piece for any collector!

Update: finally sold for 322 GBP ($496).

Regla de cálculo de cuatro caras

Muy rara, esta pieza ha sido vista en ebay. El precio final sin duda será alto… y mientras tanto he recopilado las imágenes e información para todos nosotros.

¡Una impresionante pieza para cualquier coleccionista!

Actualización: finalmente vendida por 322 GBP ($496).