| Fowler Calculator Ltd. was founded by William H. Fowler in 1898. The Manchester based company manufactured slide rules, scientific and mathematical instruments. Fowler’s Universal Calculator is a circular variation of the commonly known linear slide rule. Used mainly by engineers, scientists and engineers The Fowler has only two controls, one to rotate the scales (all in one piece) under a fixed red radial hairline, and the other to rotate a transparent disc bearing a black hairline. By setting the angular separation of the two hairlines to represent a given multiplication factor (i.e. logarithm), one can then use this separation to multiply or divide any number by that factor. There are also scales for reckoning cube roots, reciprocals, logarithms, sines and tangents. Being circular, they pack more length into less space, allowing a higher precision than a straight slide rule of similar compactness. |
