An Element of Order
Julius Lothar Meyer and his not-so-famous periodic table. (Yale University, Harvey Cushing/John Hay Whitney Medical Library; Edgar Fahs Smith Collection, University of Pennsylvania Libraries)
The one-word difference, the shift from “periodic” to “stepwise” triggered a heated dispute between the two men that ran throughout much of the 1870s and which was extensively commented on in chemistry journals across Europe. Mendeleev knew he had to persuade the Germans, who by that time were preeminent in chemistry. In 1871 he published the full version of his work—with now detailed predictions of three new elements—in Liebigs Annalen. The battle heated up in the journal of Germany’s new chemical society, Berichte der deutschen chemischen Gesellschaft.
Mendeleev stood fast in refusing to give Meyer any credit. “Meyer’s claims for credit were modest,” Gordin says. “He wanted some credit for being part of the process of creating a periodic system. Mendeleev wanted credit for creating the system; he didn’t think he should share that with anybody. And it’s very tricky to claim that because there were so many predecessors.”
A Russian Triumph
In his fight with Meyer, Mendeleev argued that his periodic system was independent of and more advanced than anybody else’s. And he took what no one else had done, his predictions, and emphasized those, staking his claim to priority on what he called his eka-elements: eka-aluminum, eka-boron, and eka-silicon, which filled the gaps next to aluminum, boron, and silicon. Eka-aluminum was discovered in 1875 and called gallium; in 1879 eka-boron was discovered and called scandium; and eka-silicon was discovered in 1886 and called germanium. Mendeleev had expected his predictions to come true at some uncertain future date, with any luck while he was still alive. When the first of his predictions came true, Mendeleev, says Gordin, was as surprised as anyone else.
But simply predicting new elements was not enough; Mendeleev had to convince people that prediction was the important criterion in deciding who won the race. By the 1880s he had persuaded the world that prediction made the periodic system a unique chemical tool. Even so, chemists often gave Meyer and Mendeleev shared credit for the periodic system, with each discovering it independently. Meyer and Mendeleev jointly received the Davy Medal of the Royal Society in 1882. Chemistry textbooks published at the turn of the 20th century that included the periodic table often mentioned Meyer as well as Mendeleev as the creators of the periodic system.
Only death ended the priority battle. After Meyer died in 1895, Mendeleev, who died in 1907, continued to write about the priority dispute, claiming sole ownership of the periodic system, and without Meyer few were left to argue against him. The Soviet Union’s growing economic importance in the 1930s helped tip the balance further, as did the Nazi purge of German science and their expulsion of Jews, socialists, and other undesirable scientists. By the 1950s the Soviet Union was second only to the United States in terms of quantity and quality of work in chemistry, and Soviet chemistry journals referred to the periodic table as Mendeleev’s system of chemical elements. Mendeleev had become the undisputed father of the periodic table.
Michal Meyer is editor in chief of Chemical Heritage. This feature is based on a lengthy interview with Michael D. Gordin, professor of history at Princeton University, about his past and current work in the history of science.