Julius Lothar Meyer
In 1869, Dmitri Mendeleev published a periodic table of all known elements (he predicted several new elements to complete the table, and corrected some atomic weights). A few months later, Meyer published a revised and expanded version of his 1864 table independently, which was similar to that published by Mendeleev (Meyer had been sent a copy of Mendeleev's table earlier; Mendeleev had sent it to many well-known chemists of his day) and a paper showing graphically the periodicity of the elements as a function of atomic weight. Meyer, as well as other chemists, was doubtful about Mendeleev's periodic law, and he criticized Mendeleev for "changing existing elements' atomic weights, only regarding possibility of periodical law in its structure". However, Mendeleev's work received significant support, when the new elements were found as predicted and atomic weights accordingly.
History of Western civilization
The 1859 publication of "On the Origin of Species", by the English naturalist Charles Darwin, provided an alternative hypothesis for the development, diversification, and design of human life to the traditional poetic scriptural explanation known as Creationism. According to Darwin, only the organisms most able to adapt to their environment survived while others became extinct. Adaptations resulted in changes in certain populations of organisms which could eventually cause the creation of new species. Modern genetics started with Gregor Johann Mendel, a German-Czech Augustinian monk who studied the nature of inheritance in plants. In his 1865 paper "Versuche über Pflanzenhybriden" ("Experiments on Plant Hybridization"), Mendel traced the inheritance patterns of certain traits in pea plants and described them mathematically. Louis Pasteur and Joseph Lister made discoveries about bacteria and its effects on humans. Geologists at the time made discoveries indicating the world was far older than most believed it to be. Early batteries were invented and a telegraph system was also invented, allowing global communication. In 1869 Russian chemist Dmitri Mendeleev published his Periodic table. The success of Mendeleev's table came from two decisions he made: The first was to leave gaps in the table when it seemed that the corresponding element had not yet been discovered. The second decision was to occasionally ignore the order suggested by the atomic weights and switch adjacent elements, such as cobalt and nickel, to better classify them into chemical families. At the end of the 19th century, a number of discoveries were made in physics which paved the way for the development of modern physics – including Maria Skłodowska-Curie's work on radioactivity.