|Slide rules HOME page||COLLECTION||NON-STANDARD RULES|
|Make||Carbic (Otis King), London, England|
|Model||Model L, Serial number R1942
Model K, Serial number W7400
1. The spiral scales gave the equivalent of a slide rule 66" long.
2. There are two different models. Model K (the upper image) has two scales for multiplication and division, which reduces the amount of manipulation required during calculations. Model L (the lower image) replaces one of these with a scale of logarithms, which extends the functionality of the rule.
3. A copy of the instructions, covering both models, can be found here.
4. Dick Lyon has a web site devoted to Otis King rules and is always pleased collect information from owners and give advice.
Close-up - Model K
Close-up - Model L
|Manufacturing date||Model K, mid 1960s (email from Dick Lyon)
Model L, 1955 (pencilled note inside of box)
|Material||Chrome and black metallic.|
|Scales||Two spiral scales the equivalent of C and D and one the equivalent of L.|
|Documentation||Original documentation came with one of the rules.|
|Condition||Both very good with original cardboard box..|