ROTH, JUSTUS LUDWIG ADOLPH

(b. Hamburg, Germany, 15 September 1818; d. Berlin, Germany, 1 April 1892)

geology, petrology.

Roth was the son of a pharmacist. He studied pharmacology and geology at the universities of Berlin, Tübingen, and Jena. His professors included Heinrich and Gustav Rose and Quenstedt. He obtained his Ph.D. in 1844 at Jena. From 1845 to 1848 he directed the Roth’sche Apotheke in Hamburg, which he had inherited from his father, but then leased it and moved to Berlin to dedicate himself entirely to the earth sciences.

During an assistantship at a pharmacy in Dresden, Roth published his first treatise, Die Kugelformen im Mineralreich … ( 1844), a publication to which the painter Ludwig Richter contributed some figures. In 1848 he helped to organize the Deutsche Geologische Gesellschaft and was its secretary from 1849 to 1866. Following a stay in Naples (1855-1856), he published his monograph Der Vesuv und die Umgebung von Neapel (1857).

Roth combined his knowledge of chemistry and petrography to produce a collection of all available rock analyses—Die Gesteins-Analysen in tabellarischer Übersicht (1861)—and a critical evaluation of analytical methods and results. In this classification of rocks he tried to combine their chemical, mineralogical, and geological properties. In 1861 he obtained his Habilitation at the University of Berlin, and he illustrated his lectures there with the carefully collected specimens from his private collection.

Excursions to the volcanic provinces of Germany gave Roth an opportunity to apply his knowledge of recent volcanism to the fossil volcanoes of the Eifel. Following the death of Mitscherlich, his mentor at Berlin, Roth edited his manuscripts on volcanology. In 1867 Roth was appointed extraordinary professor at the University of Berlin. In the same year (during which his first wife died) he was made a full member of the Royal Prussian Academy of Sciences.

Roth’s lifelong goal was to write an advanced textbook on general and chemical geology. His Beiträge zur Petrographie der plutonischen Gesteine (Berlin 1869, 1873, 1879, 1884) were milestones in this project; and with various research reports, especially his comprehensive study “Über die Lehre vom Meta-morphismus …,” he contributed original work on metamorphic rocks and the processes of metamorphism. In 1879 he published the first volume of his masterpiece, Allgemeine und chemische Geologie.

In 1887, when the last part of the second volume of his monumental handbook of petrography, Allgemeine und chemische Geologie, appeared, he was appointed full professor of petrography and general geology at Berlin. Only the first part of Roth’s third volume was published (1890) during his life. Following his death, his daughter Elisabeth edited the second part, which Roth had prepared, and wrote supplements to previous volumes. Roth was representative of his time in that his publications were of three types: original papers on many topics, but primarily on petrography, his preferred subject; papers of a monographic or textbook nature; and popular books or articles.

Roth’s main contribution was in the field of systematic petrography. He was for two or three decades the leading specialist in this field, and thus a predecessor of Rosenbusch.

BIBLIOGRAPHY

I. Original Works. Roth’s major works are Die Kugelformen im Mineralreiche und deren Einfluss auf die Absonderungsgestalten der Gesteine. Ein Beitrag zur geognostischen Formenlehre mit Rücksicht auf Landschaftsmalerei (Dresden-Leipzig, 1844); Der Vesuv and die Umgebung von Neapel. Eine Monographie (Berlin, 1857); Die Gesteins-Analysen in tabellarischer Übersicht und mit kritischen Erläuterungen (Berlin, 1861); “Über die Lehre vom Metamorphismus und die Entstehung der krystallinischen Schiefer,” in Abhandlungen, Akademie der Wissenschaften, Berlin, Phys. Cl. (1871), 151–232; Allgemeine und chemische Geologie, 3 vols. (Berlin, 18791893), I, Bildung und Umbildung der Mineralien. Quell-, Flussund Meerwasser. Die Absätze (Berlin, 1879); II, pt. 1, Allgemeines and ältere Eruptivgesteine (Berlin, 1883); II, pt. 2, Jüngere Eruptivgesteine (Berlin, 1885); II, pt. 3, Krystallinische Schiefer und Sedimentgesteine (Berlin, 1887); III, pt. 1, Die Erstarrungskruste and die Lehre vom, Metamorphismus (Berlin, 1890); III, pt. 2, Verwitterung, Zersetzung und Zestörung der Gesteine (Berlin, 1893); and “Die Eintheilung und die chemische Beschaffenheit der Eruptivgesteine,” in Zeitschrift der Deutschen geologischen Gesellschaft, 43 (1891), 1–42.

II. Secondary Literature. On Roth and his work, see Ahlenstiel, “Justus Roth,” in Jahresheft des Naturwissenschaftlichen Vereins für das Fürstenthum Lüneburg, 12 (1890–1892), 42–44; T. Liebisch, “Justus Roth,” in Neues Jahrbuch für Mineralogie, Geologie, und Paläontologie, 2 (1893), 1–20; and A. Rothpletz’s article in Allgemeine deutsche Biographic, LIII, 533–534.

G. C. Amstutz