Cramer, Johann Andreas

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(b. Quedlinburg, Germany, 14 December 1710; d. Berggiesshiibel, near Dresden, Germany, 6 December 1777)


Cramer’s father, who was leaseholder of the state ironworks in Quedlinburg, introduced him to metallurgy, in which he took an immediate interest. When Cramer was fourteen, his father died; he was then sent to the Johanneum in Hamburg, where he received an excellent grounding in natural science.

Upon completing secondary school, Cramer began to study medicine but became dissatisfied with the subject. He took up legal studies, although he also attended lectures on chemistry and metallurgy. He had little professional success as a lawyer, and his frequently brusque manner intimidated many clients. As a result he had much free time, which he used to visit mines and foundries in the Harz region and to broaden his knowledge of analytical chemistry. This hobby so captivated Cramer that, at the age of twenty-four, he gave up his legal practice and entered the University of Helmstedt with the intention of becoming a chemist and metallurgist. After concluding his studies, he went to Leiden to lecture on analytic chemistry.

At the same time Cramer worked on a textbook, the first of its kind, which was published in 1737. Entitled Elementa artis docimasticae, the profusely illustrated work encompassed the entire art of assaying in two parts, one theoretical and one practical. In the preface he referred to the works of Agricola, Lazarus Ercker, and Stahl. All the instruments and apparatus of contemporary analytical chemistry were depicted and described exactly.

In the Elementa, Cramer first described the use of the blowpipe in smelting small amounts of substances and in analyzing them. The sample was heated to glowing over charcoal, and in many cases borax beads were also utilized. The blowpipe, which was made of copper, included a bulge to collect the saliva secreted during the heating.

In 1738 and 1739 Cramer made a long trip through England to learn more about the subject, and he gave lectures in London. After further travels he returned home and in 1743 was appointed director of the Brunswick Mining and Metallurgy Administration in the Harz mountains. In addition to his official duties, he taught chemical analysis, eventually gathering a school around himself. His impetuous nature brought him many enemies, however, and as a result he lost his post for a time. Nevertheless, Cramer declined an offer from Russia and worked for only a short time in Prussia. He was asked to return to his previous post but became disgusted with it because of the intrigues in which it involved him. In 1774 he accepted a new position in Saxony, and from there he went for two years to Hungary. He returned, ill, to Germany in 1777 and died of dropsy at the end of that year.


Cramer’s main work is Elementa artis doeimastieae (Leiden, 1737; 4th ed., 1744), translated into German by Christlieb Ehregott Gellert as Anfangsgrunde der metal-lurgischen Chemie,t 2 vols. (Leipzig, 1751 – 1755).

There is a biography in J. R. Partington, A History of Chemistry, II (London, 1961), 710–711; and III (London, 1962), 36.

GÜnther Kerstein