These numbered and lettered rods came in a military collection but I can't work out what they are. They are probably not military but worth asking. Thanks for looking
Actual knowledge: none. Pure and fevered speculation: some kind of two-way cipher method for generating codes. Do those holes look as thought they have/could receive pegs of some kind? How many rods and do they all begin with a unique single letter?
Yes They appear to be a late set of Napier's rods, also known as Napier's bones (because of the original material used). A very early calculating system first introduced in the early 17trh century but still in use in the early 20th. It gave rise to both the slide rule and log tables both of which were easier to use but less accurate. The tubular Otis King Calculator in the 20th century. finally produced a device with the convenience of a slide rule and the precision of Napier's rods. If in a military collection they could have been used by an engineer or an artilliarist but one who had a table to lay them out on A cyphering system would have alphabetic characters in greater numbers
Hi Charley that's what I was thinking there are 14 rods with different letters at the start when you rotate the rod the letters/numbers change.
Perhaps this fits the bill a bit better? The rods are parts of an early code slide rule. I have no idea who made it or which country may have used it. Each of your rods should have four sides with different characters and numbers. But you can see in this picture that rod X shows the side with the same characters as those shown on your rod X (first pic in post #4). I'm guessing if you roll your rods you can match them to the characters in this picture. Did the sleeve under them in your pictures come with these rods? And if so are there any markings on the sleeve? Hope this gives you a lead you can use.