Collection of pages from K&E catalogs for the early 4071 Family of Slide Rules


Before K&E had their numbering scheme figured out for the 4000 series rule they had a series of duplex slide rules that were the predecessors of the 4088 polyphase duplex slide rules. These rules scattered all over the model numbers series and used numbers that were used again by completely different slide rules later. There were one set of numbers used in 1901, added to in 1903 and modified in 1906. In 1909 the number set was reduced and changed again.

These slide rules were constructed on a mahogany frame with celluloid laminated to the surface. The markings are engine divided. The slide rules without trig scales did not have laminate on the top and bottom edges. The rules with trig scales did have laminate on the edges and they also had the L scale on the top edge until 1913. The hard bound catalog for 1913 shows the L scale on the edge while the soft bound version of the 1913 catalog describes the L scale being on the rear of the rule even though the illustration does not show that.

The 1901, 1903, 1906, and 1909 catalogs show the rule with straight end brackets. From 1913 on the catalogs show L shaped end brackets.

The clam shell cursor was being introduced in 1901. The catalog that year shows chisel and clam shell style cursors for the same rule with a different model numbers. The 1915 catalog showed the introduction of the all glass cursor.

Scale sets:

Without trig scales:

With trig scales before 1913:

With trig scales after 1913:

Model Numbers:

The 4xxx series of numbers were introduced in 1901. Pre 1901 model numbers of some 4071 family members are:

1901: The family is expanded to include a set of rules with second Trig slides and adds a 20" version.

1903: The 20" inch version is offered with dual slides

1906: 8" and 16" rules were introduced and rules with trig scales were introduced.

1909 - 1915: The group of rules was pared down to the following model numbers.


The following is a brief history of the 4071 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 4071 family of slide rules:

Link to scans of 4071 Old Family of Slide Rules