Collection of pages from K&E catalogs for the Universal
(4090 & 4091) Family of Slide Rules
The Universal slide rule is an early duplex slide rule with a unique dual slide system. It was offered in a 10 inch model (4090) and a 16" model (4091) long.
- Front: A = B C = D DF = C S = A
- Rear: A = BI CI = D CF = CIF L T = D
Note: The CF, CIF and DF scales are folded at the square root of 10 not pi as later rules.
The Fall issue of the 2001 Oughtred Society Journal has an article on this group of slide rules by Bob Otnes and Bob DeCesaris.
The 4090 first appeared in the 1901 catalog and last appeared in the 1911 catalog.
The following is a brief history of the 4090 family of slide rules as is told in the K&E catalogs that are available at this time. Exact timing is not possible because of the time between catalogs.
Links to catalog pages for the 4090 family of slide rules:
Link to scans of 4090s