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Christian Otto Mohr was an engineer whose work connected graphical methods with the analysis of stressed materials. Mohr's circle represents the normal stress and shear stress on differently oriented planes by points on a circle, turning a change of coordinates into a geometric construction. TU Dresden's historical account relates this construction to his 1882 work on the representation of stress and deformation.^[ref]

For a two-dimensional stress tensor, the circle has centre $({\sigma }_x+{\sigma }_y)/2$ and radiusIts horizontal intercepts give the principal stresses. This makes Mohr's circle useful for seeing both extremal stresses and the relation between plane orientation and the components of stress.

Günter Zumpe was a civil engineer and professor of mechanics and surface structures at TU Dresden. His institutional obituary records his long association with that university.^[ref]

His historical article on Mohr's circle connects Christian Otto Mohr's work to the graphical representation of stress. The construction turns components of a two-dimensional stress tensor into a circle whose intercepts give the principal stresses. Zumpe's account places this useful engineering calculation in the history of mechanics, including Mohr's 1882 article.^[ref]