Otis King's Cylindrical Slide Rule

This is a stock photo of an OK. I will insert a photo of mine later

I just opened the latest issue of the Journal of the Oughtred Society.  This issue has a picture of an Otis King (OK) slide rule on the cover. I have to unpack mine and take some pictures. I think the most interesting Otis King that I have is the Model N.  It is an early production serial #8365 with the holder 422 scale and the cylinder 424 scale. It is an all chrome plated model with white numbers on a black background scales. It came in a coffin case with the Holburn Viaduct address inside the lid. Mine is in very good condition. According to the JOS article this month it looks like there are three other Model Ns that have been recorded in the literature. However, according to the Dick Lyons table of OKs (Click here).  I found 11 type Ns listed with two of those being white numbers on a black background.

I remember when I bought this OK in Denver at a store on "Antique Row" on South Broadway about 15 years ago. I think the store was called the "Packrat".  I was in Denver doing some forensic work for a client located downtown and had some time to kill between meetings.  I had heard there was one antique store on South Broadway that specialized in scientific instruments.  The store was crammed full of gadgets. There were many pieces of surveying equipment or other pieces related to the mining industry. I can highly recommend it if the store is under the same management.  Prices were a bit steep there. It has been a long time and Ebay wasn't really around then.   I knew this particular OK was different than most of the other OKs that I had seen up to that point. Much has been published about OKs in the literature since then. My suspicion was well founded.  There is something about an OK in the way it feels and moves as you operate it that is very satisfying compared to many other slide rules.