Well preserved and working Hamann Manus R Calculator. Germany, 1955

Great pinwheel calculator with green enameled metal sheet and solid cast-iron base. This is a Hamann Manus R machine, a calculator with a mechanism similar to the one Willgodt T. Odhner developed in the late 19th century, based on the Leibniz arithmometer. The calculator boasts a fine design and is quite remarkable because of its original emerald-green color and great condition. It works very well, fluidly and softly. The Hamann Manus calculator was designed by Christel Hamann, a famous German engineer born in 1870. Hamann was responsible for the development of some of the most popular calculator of the early 20th century: the Hamann itself, the Gauss and the Mercedes Euklid. After World War I the engineer joined the Berliner De Te We (Deutschen Telephonwerke- und Kabelindustrie AG) where he developed a new calculating system that allowed an automatic division. The first machine ever with this kind of mechanism was precisely the Hamann Manus, launched in 1925. The calculator that we can see in these images bears the manufacturers name and model painted white to the left of the digit levers: De Te We Hamann Manus R. The lettering is typical of the brand. The digit numbers are also white and stand out nicely on the green background. The levers bear white and red bakelite caps, and the markers are made of bone-white bakelite. All these component parts workd perfectly and so do the chromed-metal pieces. The back of the calculator is made of black hammered-finished iron, solid and sturdy. Perfect to provide any desk with style, this calculator is a witness of the technological history of the 20th century.