PELTIER, JEAN CHARLES ATHANASE

(b. Ham, France, 22 February 1785; d. Paris, France 27 October 1845)

physics.

Peltier was born to a poor family; his father earned a living as a shoemaker. A quick intelligence and perseverance were displayed at an early age, as were mechanical skills. His formal education, however, was limited to the local schools. At the age of fifteen he was apprenticed to a German clockmaker named Brown in Saint-Quentin. He was refused permission to study and was generally ill-treated; after two years, in 1802, his father removed him from this position and apprenticed him in Paris to another clockmaker, named Méra, who had worked for A.L.Brequet. After an attempt to enter the army, which was prevented by his mother’s disapproval, Peltier attracted the attention of Brequet and entered his employ in 1804. In 1806 Peltier established his own shop and married a Mile Dufant. The death of his wife’s mother in 1815 brought him a modest inheritance, which was sufficient for their needs, and he retired.

Even while working at his trade, Peltier read broadly; when he retired, he devoted his attention to a wide range of studies and began to compose a Latin grammar. He then become interested in the phrenology of Franz Gall and was inspired, at age thirty-six, to study anatomy in order to obtain a more complete knowledge of the structure of the brain. He attended a number of vivisection demonstrations by Magendie, in which electricity was used to stimulate nerves. These demonstrations led Peltier to the study of electricity, which he pursued for the last twenty years of his life.

Peltier’s first scientific paper was delivered to the Academie des Sciences in 1830. In it he showed that chemical effects can be obtained from a dry pile if the surface area of the plates is sufficiently large. This work also showed that Peltier had some understanding of the difference between current and voltage, with which electricians were to struggle for another ten years.

Stimulated by the work of Nobili, Peltier, constructed a sensitive galvanometer to measure the conductivities of antimony and bismuth for small currents. Peltier’s use of small samples of these nonductile materials was fortunate because the anomalous behavior of these materials led him to construct a thermoelectric thermoscope and to measure the temperature distribution along a series of thermocouple circuits. He discovered that a cooling effect can take place at one junction and excessive heating at the other. He then confirmed this discovery by using an air thermomter in place of the thermoscope.

Peltier did not pursue the effect he had discovered, and its importance was not fully recognized until after the thermodynamic work of William Thomson twenty years later. He did, however, write a paper on thermoelectric piles, and he spent some time studying the relations between static and dynamic electricity.

Peltier’s remaining scientific endeavors fell into two major categories: microscopy and meteorology. His work in microscopy was an outgrowth of his anatomical and physiological interests; most of his observations were on various animalcules. In meteorology he made numerous measurements of electrical charges in the atmosphere and developed a theory that accounted for various cloud and storm formations on the basis of charge distribution. In 1842 he conducted a field trip to obtain such measurements. A cold resulting from this trip left him in a weakened condition, from which he never recovered.

BIBLIOGRAPHY

I. Original Works. A bibliography of more than 60 papers by Peltier is contained in the Royal Society Catalogne of Scientific Papers, IV, 814–817. His discovery of the “Peltier effect” appears in “Nouvelles experiences sur la caloricite des courants electriques,” in Annales de chimie, 56 (1834), 371–386.

II. Secondary Literature. A memoir by Peltier’s son, F. A. Peltier, Notice sur la vie at les travaux scientifiques de J. C. A. Peltier (Paris, 1847), was translated by M. L.Wood in Report of the Board of Regents of the Smithsonian Institution (1867), 158–202.

Bernard S. Finn