Julius Lothar Meyer

The German chemist Julius Lothar Meyer (1830–1895) was the first to develop a periodic table of chemical elements. Working independently of Russian scientist Dmitri Mendeleev, who produced a similar table at about the same time, and putting to use new insights into the chemical structure of matter, Meyer created a periodic table that, in arraying elements by atomic weight, resembles the table that is referenced today.

Julius Lothar Meyer was born in the town of Varel, in the Grand Duchy of Oldenburg (now in northwestern Germany), on August 19, 1830. His father, Heinrich Friedrich August Jacob Meyer, was a prominent town doctor, and his mother was the daughter of another physician. Meyer, who preferred using his middle name, was the fourth of seven children. His family had the money to give him a top-notch education, beginning in a local private school; when he switched to public school, his classes were supplemented by lessons in Latin and Greek. When he began to suffer from severe headaches, his father suggested that he discontinue strenuous academic studies temporarily. In their place, he used his influence to get his son a job as a gardener at the palace of the Grand Duke.

From Gymnasium to Medical School

The strategy worked; Meyer's headaches ended and he enrolled at the Oldenburg Gymnasium, an institution with a classical curriculum that spanned what in the United States would include the high-school and college years. He graduated in 1851 and promptly headed for the University of Zurich in Switzerland, where he enrolled in medical classes. He transferred to the University of Würzburg in southern Germany in 1853 and attended lectures given by the great medical sociologist Rudolf Virchow. Although Meyer earned an M.D. degree there in 1854, he did not declare his education finished. Carl Ludwig, one of his professors in Zurich, had encouraged Meyer to study physiological chemistry—the chemistry of living beings—so he headed for the University of Heidelberg, where he studied with Robert Bunsen (for whom the Bunsen burner is named).

Bunsen was one of Germany's leading experts on gas analysis, and his teaching inspired Meyer to turn his interest to pure chemistry. Meyer wrote a dissertation titled Ü ber die Gases des Blutes (“On the Gases of the Blood” ), which earned him a Ph.D. from Würzburg. At the time, the universities of Würzburg and Heidelberg were home to a number of major scientists studying physical chemistry, and Meyer took classes from or attended lectures by all of theml. He then undertook an investigation into a key medical-chemical problem that was poorly understood at the time: the deadly effect of carbon monoxide on the blood. That work earned him a second Ph.D., this one from the University of Breslau (now the University of Wroclaw in Poland).

Finally, Meyer considered himself ready to teach. After issuing a paper, “Die chemischen Lehren von Berthollet und Berzelius” (“The Chemical Teachings of Berthollet and Berzelius,” the latter being the scientist who had devised the system of common one- and two-letter abbreviations for chemical elements), he was qualified to begin giving courses at Breslau, where he remained until 1865, becoming director of the school's physiology laboratory. He continued, however, to attend conferences and stay up to date on new research developments relevant to his interests. The Karlsruhe Congress of 1860, a large scientific conference, proved especially important. The conference was devoted to the emerging field of the classification of chemical elements. At the time, it was recognized that matter was composed of different elements that had different atomic structures, but there was no organized way of dealing with the diversity that the physical forms of matter presented.

Breakthrough at Conference

Meyer's book contained something new: a table of elements ordered by atomic weight (the weight of all the atomic particles a molecule of an element contains, now known as relative atomic mass) and by valence (the tendency of particles that are part of an element to combine with those of other elements). Using these principles, Meyer left a blank space in his table for an element that was not yet known but that, he guessed correctly, remained to be discovered (it has since been shown to be germanium, with an atomic weight of the predicted 73.1). His table covered only 28 common elements, but it included the important insight that they could be grouped into families according to their valences.

In 1868 Meyer published a paper that added to the scope of his table, which by now had been expanded to 52 elements. Soon he became aware that a Russian scientist, Dmitri Mendeleev, was working along similar lines. The outbreak of the Franco-Prussian War in 1870 interrupted Meyer's research as he was forced to return to his earlier specialty as a physician: he organized an emergency clinic on the Polytechnic Institute campus to treat wounded German soldiers and worked in its operating room himself.

It was Mendeleev who, in 1869, published the first complete periodic table of the elements in the form in which it remains known. The question of who deserved to be credited as the creator of the periodic table was debated at the time and remains an open issue today. Mendeleev's publication preceded Meyer's comprehensive formulation by several months, but Meyer had made crucial breakthroughs in advance of the Russian scientist. Meyer's 1870 paper “Die Natur der chemischen Elementen als Function ihrer Atomgewichte” (“The Nature of Chemical Elements as a Function of Their Atomic Weight” ) established the ordering of the periodic table by atomic volume and atomic weight (known as periodicity, the source of the term “periodic table” ), and presented the ordering in an elegant tabular form. Mendeleev's work, too, was delayed by war for much of 1870.

Jointly Honored with Mendeleev

Although the two scientists briefly debated who had come first, Meyer acknowledged the priority of Mendeleev's paper, and Mendeleev is known today as the table's originator. At the 1882 meeting of the Royal Society in London, the pair shared the Davy Medal and were jointly celebrated for their accomplishments. Meyer received a variety of other honors later in his career, including foreign honorary membership in England's Chemical Society and corresponding memberships in the Academies of Science of Prussia and St. Petersburg, Russia, in 1888 and 1891, respectively. In 1892, the duke of WOrttemberg bestowed upon Meyer honorary membership in the principality's hereditary nobility.

In 1876 Meyer became a professor at the University of Tübingen, where he taught for the remainder of his career. By the late 1870s he was a widely influential and respected figure in German science, and at Tü he supervised the doctoral theses of more than 60 graduate students. He continued to work on the problems of atomic weight and its relation to the classification of elements, refining his research and in 1890 publishing a less-technical summary, Grundzüge der theoretischen Chemie (“Foundations of Theoretical Chemistry” ). He was chosen as rector of the university in 1895.

Meyer's research interests in his later years were not restricted to the periodic table. He and his students worked on such topics as boiling points, solubility, and molecular volume and he was the first to propose a major advance in the understanding of the structure of the benzene atom. Meyer also personally invented many pieces of chemistry laboratory apparatus that were adopted by other scientists.

In his old age, Meyer continued to enjoy gardening, which he had practiced ever since his period of palace employment as a teenager. He gave general lectures, not oriented toward science specifically, on the state of higher education in Germany in his later years. Meyer remained active until his sudden death from a stroke on April 11, 1895. A period obituary reproduced by Scientific American noted that “a great chemist has passed away from us; his work remains, and that work will ever be held in remembrance.”

Books

Complete Dictionary of Scientific Biography, Volume 9, Scribner's, 2008.

Online

Chemical Heritage Foundation website, https://www.chemheritage.org/ (November 5, 2016), “Julius Lothar Meyer and Dmitri Ivanovich Mendeleev.”

Royal Society of Chemistry website, http://www.rsc.org/ (November 5, 2016), “Julius Lothar Meyer—The First Identifier of Periodicity?”

Scientific American online, https://www.scientificamerican.com/ (November 5, 2016), M.M. Pattison Muir, “Professor Lothar Meyer.”❑

(MLA 8th Edition)