Bidspirit auction | Otis King Model K Cylindrical

Otis King Model K Cylindrical Slide Rule with Case - A vintage Otis King Patent cylindrical slide rule, Model K, manufactured by Carbic Ltd. of London, England. The instrument comprises two telescoping metal cylinders, one finished in polished chrome plating and the other in a black matte coating. Logarithmic scales are printed in black on a cream-coloured ground, arranged spirally around the cylinders. The ends are fitted with knurled metal caps to facilitate rotation and extension. The scale is printed with the text OTIS KING'S PATENT No 183723 and the top of one scale is marked with the model designation K and the number 16:11. The item is accompanied by its original brown leatherette tubular protective case featuring a metal snap-fastener closure. Length when closed: approximately 15 cm.