This is a good example of a 600 mm Japanese slide rule from about 1960.

Japan's slide rule manufacturing industry started as a result of a visit in 1894 to Europe by two Japanese engineers to look at European industry. They brought back information about the French Mannheim design and they explored various materials, in particular bamboo for slide rules. In 1895 they started the Hemmi Keisanjaku (Sun) manufacturing company, which became one of the largest slide rule manufacturers in the world. The first Sun patents were for a bamboo Mannheim (France) type slide rule. Hemmi also adopted systems Rietz and Darmstadt for its double-sided 'Duplex' scale design.

For a number of years the Hemmi cursor design left the frame open on the left, so that the right hand which moved the cursor did not cover the window (this would give left hand users a problem!)

Made by Hemmi in Japan about 1960. Hemmi made many special-purpose rules, including surveying, civil, chemical, electronic, and mechanical engineering.

Slide rule and case, bamboo / plastic / metal / leather, designed and made by Hemmi, Japan, 1955-1965

A slide rule consisting of three parallel lengths of laminated bamboo held in place at each end by metal brackets and screws. The middle length of bamboo slides between the other two lengths which are secured in a fixed position. The cream coloured rule is doubled sided with measurements indicated by blue and red markings. A chrome-framed glass cursor can be moved along the length of the rule. The slide rule is stored in a brown leather case. The opening at one end is closed with a leather flap which is secured by threading it through a leather strap. The base of the case is flat with the upper stitched on three edges to created the case. The body of the case is lined with cardboard.

Designed: Hemmi Slide Rule; Japan

Made: Hemmi Slide Rule; Japan; 1955 - 1965

H9443