K e slide rule dating
K e slide rule dating
The rule fits in a brown leather case, which is marked on the front of the flap: 4092-3S.This ten-inch mahogany linear slide rule is coated with white celluloid on the front and both sides of the slide. The slide has B and C scales on one side and S, L, and T scales on the other. The indicator is glass with a plastic frame, of the style used by Keuffel & Esser between 19, based on the patent indicated by the mark on the top edge of the frame: K&E.
This nice rule arrived in rough shape: the cursor had crumbled and rusted, and left a stain on the rule. Young, MIT '07, 356 Mass Ave." (A small "WAY" is also gently inscribed into the wood on the back.) Assuming "'07" was engineer Young's class year, it suggests the rule dates to 1904-1907. K&E introduced a frameless cursor around 1914-15, and initially mounted the cursor on metal blocks.
This ten-inch mahogany two-sided linear slide rule is coated with white celluloid and held together with L-shaped metal end pieces.
On one side, the base has K, DF, D, and L scales, with CF, CIF, CI, and C scales on the slide. The bottom of the base is marked in red: KEUFFEL & ESSER CO.
According to Eric Marcotte, this circular was in force from 1914 to 1936.
It seems likely that he used the slide rule as a college student.
Another beautiful K&E rule, bearing hyperboic sine (Sh1, Sh2) and tangent (Th) scales for electrical engineers.
This one bears the SRT scale (radian sine & tangent), which first appears in a September 1955 revision of the K&E manual.
The serial number, 532933, dates this rule to 1935 In 1935, my grandfather was 24 years old, and worked for Carborundum in Niagara Falls, NY.
I don't know if he used this slide rule in his work, but I assume he did as slide rules weren't cheap, and not the kind of thing you'd buy just for fun - it would have cost him .35 - a whopping 0 in Y2K money!
The 1921 K&E catalog describes this slide rule: The Favorite Slide Rules are of the same pattern as No. They are an improvement over the imported rules, being made of materials seasoned here and, therefore, less liable to warp or shrink.
An interesting variation on the "Buy American" theme.
The indicator is frameless glass with plastic edges held together with metal screws. K&E stopped selling model 4092-3 in 1938, when it was priced with a leather case at .75.