Jean-Baptiste Biot

Jean-Baptiste Biot (1774-1862)

1775 On the 21st of April, Jean Baptiste Biot was born at Paris, France. He was a French physicist, astronomer, and mathematician who established the reality of meteorites, made an early balloon flight, and studied the polarization of light. He was remarked because of his special abilities for studying, approaching the most varied fields of literature and science at that time. Biot’s scientific work is focused on Maths, Physics, Chemistry and Astronomy problems.

1803 He was chosen member of Academy of Sciences as he had contributed a lot to science. Optical and electrical works deserve a special remark because of their theoretical and practical importance.

Regarding optic, he studied light polarization phenomenon when it goes through crystals and starting with the hypothesis that there is a link between the crystallization state of an object and polarization phenomena of light and established the existence of two optical axes into small crystal.

He discovered the qualitative law of rotating polarization plane for solutions. This law sets that rotation is directly proportional to substance concentration and to thickness of solution. Biot also expressed by an approximate law the wavelength influence on the power to rotate of polarization plane.

He also established saccharimetry, also elaborating a method to distinguish vegetal juices that give sugars analogous to cane sugar of those which give sugars analogous to that of grape. He also accurately determined the quantity of crystallized sugar that remains into molasses. This method was used by medicine in order to determine diabetes.

1810-1811 He wrote an elementary treatise of physical astronomy (“Traite elementaire d’astronomie physique”).

1816 He wrote a treatise of experimental Physics and mathematical physics (“Traite de physique experimentale et mathematique”).

1820 Related to electricity, Biot and Savart measured the intensity of magnetic field created by a linear current, so experimentally discovering one of the basic laws of electromagnetism. This law expresses the fact that magnetic field intensity created by a linear current, varies directly proportional to current intensity and inversely proportional to the distance from the current-carrying conductor to than external side. Then, this law was generalized by Laplace.

1823 He wrote researches about numerous Egyptian astronomy subjects (“Recherches sur plusieurs points de l’astronomie egyptienne”).

1861 “Short Hystory of Chinese Astronomy” (“Precis de l’histoire de l’astronomie chinoise”)

1862 “Studies on Indian and Chinese Astronomy” (“Etudes sur l’astronomie indienne et sur l’astronomie chinoise”). On the 3rd of February, Jean Baptiste Biot passed away.

Biot was not an isolated savant, he liked to collaborate; so, he studied together with Argo problems related to geodesy and Physics, with Thenard Chemistry problems, with Melloni radiant heat and with Puillet diffraction phenomenon.

As a human being, the next event is representative for Biot. When Volta exposed to Academy in Paris, where Napoleon was, too, his theory on galvanic electricity, it was proposed for him to be given a golden medal. Academy Commission report was typed by Biot and it is his merit because a big amount was allocated for Volta’s researches.

In this way Biot expressed his feelings for his foreign colleagues, even if personally did not completely agree all Volta’s findings.

 

 

Bibliography:

    1. Jean Baptiste Biot (1775-1862), ro.biography.name