MüLLER, FRANZ (FERENC), BARON DE REICHENSTEIN

(b. Nagyszeben, Transylvania [now Sibiu. Rumania], 1 July 1740; (d. Vienna, Austria, 12 October 1825)

chemistry.

Müller, the son of a treasury official, was educated in Nagyszeben and then studied law in Vienna. By then he had become interested in chemistry and mineralogy and went to Selmecb´nya (Schemnitz, in Hungary), where a short time earlier one of the world’s first mining academies had been opened. There he studied mining and metallurgy under N. J. Jacquin. After completing his studies in 1768, Müller entered the service of the state saltworks in Transylvania; later he was active in mining in southern Hungary. From 1775 to 1778 he was director of the state mines in the Tirol; and from 1778 to 1802 he directed all mining operations in Transylvania from his office in Nagyszeben. In 1802 Müller moved to Vienna to head the council that had jurisdiction over minting and mining in Austria and Hungary. He held this position until 1818. On his retirement he received the Order of St. Stephen and the title of baron.

Müller discovered the chemical element tellurium in 1784 at Nagyszeben. For several years sylvanite, an auriferous mineral from Transylvania, had been causing problems because its processing always yielded less gold than expected. Anton von Ruprecht, a former schoolmate of Müller’s and professor of chemistry at the Selmecb´nya Mining Academy, analyzed the ore in 1782 and published his finding that it contained antimony as well as gold. Müller did not share this view, asserting in print that the substance involved was bismuth. Ruprecht responded by stating the reasons it could not be bismuth. In his next publication Müller admitted his error and announced that a new, previously unrecognized semimtel was present in the ore; he also enumerated its characteristic chemical reactions [Physikalische Arbeiten der einträchtigen Freunde in wien, I , no. 2 [1783], 63).

Müller, however, did not name the new element. Instead, he sent a sample of the ore to Torbern Bergman at Uppsala, wishing to confirm his conclusion by submitting the substance for examination to the most famous analyst of the century. Bergman reported in a letter that he was starting to work on the matter, but he died soon after. Ten years later the Berlin chemist Martin Klaproth asked Müller to send him a sample. He carried out an analysis, confirmed Müller’s finding, and gave a lecture on the subject at the Berlin Academy, where he proposed that the previously unnamed element be called tellurium.

Müller also contributed to mineralogy. He discovered a variety of tourmaline and a variety of opal that is also called Müller glass.

BIBLIOGRAPHY

Müller’s publications are listed in Poggendorff, II, 231.

Secondary sources include R. Jagnaux, Histoire de la chimie, I (Paris, 1891), 500–504; F. Szabadv´ry, Az elemek nyomában (“In the Traces of Elements”; Budapest, 1961), 142–148; and M. E. Weeks, Discovery of the Elements (1956), 303–304, also in Journal of Chemical Education, 12 (1935), 403.

F. SzabadvÁry