Nikolai Ivanovich Lobachevskii
was born 221 years ago
1st December 1792

In 1829 Nikolai Ivanovich Lobachevskii published his non-Euclidean geometry, the first account of the subject to appear in print.

Find out more at:
http://www-history.mcs.st-andrews.ac.uk/Mathematicians/Lobachevsky.html