January 1931
january – national committee modification of volstead act formed work repeal of prohibition in united states. january 2 – south dakota native ernest lawrence invents cyclotron, used accelerate particles study nuclear physics. january 3 – albert einstein begins doing research @ california institute of technology, along astronomer edwin hubble. january 4 – german pilot elly beinhorn begins flight africa. january 6 – thomas edison submits last patent application. january 22 – sir isaac isaacs sworn in first australian-born governor-general of australia. january 25 – mohandas gandhi again released imprisonment in india. january 27 – pierre laval forms government in france. january 30 – release of movie city lights starring charlie chaplin.