Bernard Riemann was a German mathematician who lived during the nineteenth century and is considered one of the most important mathematicians of his day. Analytical geometry, number theory, and differential geometry were among the fields where he made significant contributions. One of Gauss’s few students was the originator of Riemannian geometry, which Albert Einstein used to create his theory of relativity. Gauss had only a few students in total. Riemann escaped from Gottingen in 1866, during the Austro-Prussian War, and did not return for the rest of his life. In his journey to Italy, he acquired tuberculosis and died as a result.

## Z Proportions

Becca Hirsbrunner photographed this fabulously constructed Z proportions letter. Interestingly, every element but the diagonal bar can be rationalized.