Johan Carl Wilcke (6 September 1732 – 18 April 1796) was a Swedish

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

Biography

Wilcke was born in

Wismar Wismar (; ), officially the Hanseatic City of Wismar () is, with around 43,000 inhabitants, the sixth-largest city of the northeastern German state of Mecklenburg-Vorpommern, and the fourth-largest city of Mecklenburg after Rostock, Schwerin and ...

, son of a clergyman who in 1739 was appointed second pastor of the German Church in

Stockholm Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...

. He went to the German school in Stockholm and enrolled at the

University of Uppsala Uppsala University (UU) () is a public research university in Uppsala, Sweden. Founded in 1477, it is the oldest university in Sweden and the Nordic countries still in operation. Initially founded in the 15th century, the university rose to s ...

in 1749. He spent the years from 1751 travelling abroad and received the '' magister'' degree from the

University of Rostock The University of Rostock () is a public university located in Rostock, Mecklenburg-Vorpommern, Germany. Founded in 1419, it is the third-oldest university in Germany. It is the oldest university in continental northern Europe and the Baltic Se ...

in 1757, after having published the dissertation ''De electricitatibus contrariis''. In 1759 he became the first "Thamian lecturer" of experimental

physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...

at the

Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences () is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for promoting nat ...

, a position created through a donation from the wealthy

merchant A merchant is a person who trades in goods produced by other people, especially one who trades with foreign countries. Merchants have been known for as long as humans have engaged in trade and commerce. Merchants and merchant networks operated i ...

Sebastian Tham, and a member of the academy. He became a titular professor in 1770, and permanent secretary of the Academy of Sciences in 1784. He died in Stockholm in 1796. His two areas of significant research were

electricity Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

and

caloric theory The caloric theory is an obsolete scientific theory that heat consists of a self-repellent fluid called caloric that flows from hotter bodies to colder bodies. Caloric was also thought of as a weightless gas that could pass in and out of pores ...

. In 1762 he invented an

electrostatic generator An electrostatic generator, or electrostatic machine, is an electric generator, electrical generator that produces ''static electricity'', or electricity at high voltage and low continuous current. The knowledge of static electricity dates back t ...

that was a first version of the

electrophorus In electromagnetism, an electrophorus or electrophore is a simple, manual, Capacitor, capacitive, electrostatic generator used to produce Electric charge, charge via the process of electrostatic induction. A first version of it was invented in 1 ...

, a device named and popularized in 1775 by

Alessandro Volta Alessandro Giuseppe Antonio Anastasio Volta (, ; ; 18 February 1745 – 5 March 1827) was an Italian chemist and physicist who was a pioneer of electricity and Power (physics), power, and is credited as the inventor of the electric battery a ...

. In 1772 he calculated the

latent heat Latent heat (also known as latent energy or heat of transformation) is energy released or absorbed, by a body or a thermodynamic system, during a constant-temperature process—usually a first-order phase transition, like melting or condensation. ...

ice Ice is water that is frozen into a solid state, typically forming at or below temperatures of 0 ° C, 32 ° F, or 273.15 K. It occurs naturally on Earth, on other planets, in Oort cloud objects, and as interstellar ice. As a naturally oc ...

. In 1781, he coined the concept and term of "specific heat" (''Specifica-varme''), in analogy with the term "specific gravity" (''Specifica-tyngd''). In 1789 he was elected a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the Fellows of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural science, natural knowledge, incl ...

in London.

Notes

References

* ''

Svenskt biografiskt handlexikon ''Svenskt biografiskt handlexikon'' () is a compact Sweden, Swedish dictionary of biography first published in 1873–1876 by the physician and antiquarian Herman Hofberg (1823–1883). The second, updated edition was published in 1906, under th ...

'', vol 2, p. 73

(Swedish) *
Encyclopedia.com: Wilcke, Johan Carl

External links

Johan Carl Wilcke
in Rostock Matrikelportal {{DEFAULTSORT:Wilcke, Johan People from Wismar Swedish physicists Swedish people of German descent Uppsala University alumni University of Rostock alumni Members of the Royal Swedish Academy of Sciences Fellows of the Royal Society 1732 births 1796 deaths Members of the Royal Society of Sciences in Uppsala