Karl Friedrich Mohr

Karl Friedrich Mohr (November 4, 1806 – September 28, 1879) was a German pharmacist famous for his early statement of the principle of the conservation of energy. Ammonium iron(II) sulfate, (NH₄)₂Fe(SO₄)₂.6H₂O, is named Mohr's salt after him.

Life

Mohr was born in 1806 into the family of a well-to-do druggist in Koblenz. Being a delicate child, the young Mohr received much of his early education at home, a great part of it in his father's laboratory. This experience may be responsible for much of the skill Mohr later showed in devising instruments and methods of chemical analysis. At the age of twenty-one he began to study chemistry under Leopold Gmelin, and, after five years in Heidelberg, Berlin and Bonn, he returned with the degree of Ph.D. to join his father's establishment.

Mohr's father died in 1840 at which time Mohr took over the family business. He retired from it for a life of scientific leisure in 1857, but at the age of fifty-seven some serious financial losses led him to become a privatdozent in Bonn. In 1867 he was appointed, by the direct influence of the emperor, extraordinary professor of pharmacy.

Work

and ran to many editions. His "Geschichie der Erde, eine Geologic auf neuer Grundlage" (1866), was also widely circulated.

In a paper "Über die Natur der Wärme" (1837), Mohr gave one of the earliest general statements of the doctrine of the conservation of energy:

:"besides the 54 known chemical elements there is in the physical world one agent only, and this is called Kraft (energy). It may appear, according to circumstances, as motion, chemical affinity, cohesion, electricity, light and magnetism; and from any one of these forms it can be transformed into any of the others."

Selected writings

*: - Based on Mohr's work

Further reading

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* Mohr, K. F. (1837) "Ansichten über die Natur der Wärme." "Ann. der Pharm.", 24, pp. 141–147.

* Mohr, K. F. (1876) (trans. P. G. Tait) "Views of the nature of heat." "Philosophical Magazine" 2 110-14.

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* See also [http://de.wikipedia.org/wiki/Bild:Karl_Friedrich_Mohr.pngthis site] for a different photograph of Mohr