Richard Dedekind publishes Was sind und was sollen die Zahlen? ("What are numbers and what should they be?") which includes his definition of an infinite set.[5]
The global atmospheric temperature returns to normal, five years after the 1883 eruption of Krakatoa (Krakatau). The volcanic dust veil, that has created spectacular atmospheric effects, also acted as a solar-radiation filter, lowering global temperatures by as much as 1.2 degrees Celsius in the year after the eruption.
^Maienschein, Jane (1989). One Hundred Years Exploring Life, 1888-1988: the Marine Biological Laboratory at Woods Hole. Boston: Jones & Bartlett. ISBN978-0-86720-120-8.
^Bulmer, Michael (2003). Francis Galton: Pioneer of Heredity and Biometry. Baltimore: Johns Hopkins University Press. pp. 191–196. ISBN978-0-8018-7403-1.
^Kovalevskaya, S. (1889). "Sur le problème de le rotation d'un corps solide autour d'un point fixe". Acta Mathematica. 12: 177–232. doi:10.1007/bf02592182.
^Cooke, Roger (1984). The Mathematics of Sonya Kovalevskaya. New York: Springer-Verlag. ISBN978-0-387-96030-2.
^Collingridge, Jeremy M. R.; et al. (2007). "Ink Reservoir Writing Instruments 1905–20". Transactions of the Newcomen Society. 77 (1): 69–100. doi:10.1179/175035207X163361.