Georg Mohr
Jørgen Mohr was a Danish mathematician, known for being the first to prove the Mohr–Mascheroni theorem, which states that any geometric construction which can be done with compass and straightedge can also be done with compasses alone.
1 April 1640
Born on the same birth day (1 April): Edgar Wallace • Erik Breukink • F. Melius Christiansen • Gaston Eyskens • Hillary Scott • Javier Irureta • José Rodrigues dos Santos • Loris Kessel • Nicola Roxon • Peter Collinson (film director) • Peter Law • Teddy Diaz • Walter Bahr • Wangarĩ Maathai • Yuka Kaneko
Born in the same month (April 1640): Gaspar Sanz