Fabbroni, Giovanni Valentino Mattia, 1752-1822

Italian scientist.

Sir Joseph Banks was an English naturalist and president of the Royal Society.

Fabbroni was an Italian naturalist and director of the Mint in Florence.

Giovanni Valentino Fabbroni (1752-1822) was an Italian naturalist, agronomist, economist, and politician. He was a founder and vice director of the Natural History Museum in Florence and also served as director of the Mint of Tuscany. His varied activities included electrochemical experiments that helped pave the way for subsequent developments, most significantly the invention of the battery; studies in currency, including contributions to the creation of the metric system; and proposals related to agricultural and economic reform in Tuscany. Fabbroni maintained an extensive correspondence with a wide variety of individuals in Europe and the United States.

Little is known about Fabbroni’s personal life, including his upbringing and education; a hint that he may have come from less then favorable circumstances is provided by R. Lee who wrote in her Memoirs of Baron Cuvier (1833) that, “Like most of those who have attained great celebrity, the early years of M. Fabbroni were passed in struggle and difficulty.” He was born in 1752 in Florence, Italy, where he also spent most of his adult life. In 1775, he collaborated with Felice Fontana (1730-1805) in the founding of the “Imperiale e Regio Museo di Fisica e Storia Naturale,” a natural history museum. For the next thirty years, Fabbroni served as the museum’s vice director under Fontana, who was appointed its first director.

Fabbroni was an advocate of the chemical revolution of Antoine-Laurent Lavoisier (1742-1794, APS 1775) and at the museum, which had its own laboratory, he and Fontana conducted research in pneumatic chemistry and electrochemistry. One of his research interests concerned animal electricity, which had only recently been demonstrated by Luigi Galvani (1737-1798). Fabbroni proposed that galvanism may be due solely to chemical affinities, and that electricity could be generated only by the contact of dissimilar bodies when they reacted together chemically, differed in temperature, or were rubbed together. Fabbroni’s findings, which he presented before the Accademia dei Georgofili in 1793, set the stage for a favorable reception in 1800 of Alessandro Volta's (1745-1827) voltaic pile, the first battery that produced a reliable, steady current of electricity. Fabbroni’s ideas also influenced the work of Anthony Carlisle (1768-1842), William Nicholson (1753-1815) and Humphry Davy (1778-1829, APS 1810), who may have learned of them from translations of Fabbroni’s paper published in the Journal de physique (1799), the Journal of Natural Philosophy (1800), and the Philosophical Magazine (1800). Fabbroni also often assisted Grand Duke Peter Leopold (1747-1792), who conducted scientific experiments as a hobby.

In 1778 Fabbroni wrote the first of many letters to Thomas Jefferson. Jefferson had learned of Fabbroni from their mutual friend Philip Mazzei (1730-1816) as early as 1767, and he had encouraged the young man to move to Virginia to become music teacher and tutor to his children. Fabbroni evidently was inclined to accept the offer when the Duke of Tuscany selected him to travel through England and France to observe scientific and technological progress in each nation. Frabbroni accepted the Duke’s invitation, and while there is no evidence that he ever visited the United States, he subsequently corresponded with Jefferson on a variety of topics, including meteorology and music, which Jefferson famously described in a letter to the Italian as "the favorite passion of my soul.”

In 1778 Fabbroni traveled to England, where he recorded his observations in a series of diaries. During his stay in London he became acquainted with Benjamin Franklin as well as Richard Price (1723-1791, APS 1785), Joseph Priestley (1733-1804, APS 1785), Benjamin Vaughan (1751-1835, APS 1786), and other radicals, many of whom were members of the Club of Thirteen, an intellectual club founded in the 1770s. Fabbroni apparently attended some of their meetings and he also carried their letters and parcels to Paris.

In 1780 Fabbroni published in Paris his Reflexions sur l'état actuel de l'agricolture, in which he developed new techniques of agronomy and cultivation based on procedures of pneumatic chemistry. He suggested, for example, replacing crop rotation and tilling with a series of plants grown together. The book had a considerable impact on farming in Tuscany. More generally, Fabbroni's work contributed to the process of applying chemistry to study the plant world, which eventually developed into the disciple of agricultural chemistry.

In 1783 Fabbroni became a member of the Accademia dei Georgofili, a learned society dedicated primarily to the natural sciences and agricultural reform, and the following year he commenced work as its correspondence secretary, acting as the intermediary between the Accademia and the museum. In addition, the Tuscan government frequently called on Fabbroni to contribute plans and ideas toward the improvement of Tuscany’s economy, including the location of potentially lucrative coal deposits. The scholarly works he published during this period include essays on topics such as currency, economics, and government.

Fabbroni was influential in the development of the metric system and in its introduction to Italy. In the late 1790s the French government sought to establish a mass standard that would aid in the regulation of commerce. Fabbroni was selected as a member of a committee charged with determining the mass of a cubic decimeter of water. At the time the decreed definition of the kilogram specified water at 0°C, its highly stable temperature point. In 1799, after several years of research, Fabbroni and the French chemist Louis Lefèvre-Gineau (1751-1829) redefined the temperature at which water reaches maximum density as 4°C, as opposed to 0°C. Based on their calculations, a new Kilogram was manufactured and delivered to the Archives of the Republic. The prototype was ratified, and the new standard eventually stood for the next ninety years.

Overall, Fabbroni’s activities were unsually varied. Lee wrote in her biography of Fabbroni’s friend Georges L. C. F. D. Cuvier (1769-1832), who evidently penned an eulogy for Fabbroni, that “we find [Fabbroni], at one time, charged with delicate political missions; at others, with the direction and administration of the mint at Florence [1800]; seeking the causes of pestilence, and the means of prevention; making roads, fixing conductors for lightning, and aiding the state by his counsels.” His diverse interests are also reflected in Fabbroni’s long and varied list of correspondents, ranging from artists to soldiers, aristocrats to scientists, and politicians to economists. His correspondents include, for example, Davy, Mazzei, Cuvier, Priestley, Sir Joseph Banks (1743-1820), Johann Reinhold Forster (1729-1798, APS 1793), Alexander von Humboldt (1769-1859, APS 1804), Angelica Kauffmann (1741-1807), and the Marquis de Lafayette (1757-1834, APS 1781).

Fabbroni died in 1822 in Pisa, Italy.

Humphry Davy (1778–1829, APS 1810) was a British chemist and pioneer in the field of electrochemistry. He was a major figure in the reformed chemistry movement initiated by the French scientist Antoine-Laurent Lavoisier (1743-1794, APS 1775).

Davy was the son of an impoverished Cornish woodcarver. As a youth, he was apprenticed to an apothecary-surgeon with whom he pursued a regimen of self-study that included theology, philosophy, poetics, several languages, as well as, botany, chemistry, anatomy, mechanics and physics. In subsequent years, when most of his time was occupied by scientific endeavors, Davy exhibited a particular fondness for philosophical writings and poetry. In 1799 he published his first poems.

However, it was Davy’s aptitude for scientific matters that soon attracted attention. One of the people who recognized his abilities was Davies Giddy (1767-1839), a Member of Parliament with scientific interests. Giddy eventually became Davy’s patron. He allowed his protégé access to his library; furthermore, he persuaded Davy’s master to release him from his indenture so that he could become the assistant to Thomas Beddoes, Giddy’s former teacher at Oxford.

In 1798 Davy joined Beddoes's Pneumatic Institution in Bristol which was established for the purpose of investigating the medical powers of newly discovered airs and gases. There, he made the acquaintance of fellow scientists as well as individuals with literary interests, including Samuel Taylor Coleridge (1772-1834), Joseph Cottle (1770-1853), and Maria Edgeworth (1767-1849). In 1797 Davy read Lavoisier’s Traité élémentaire de chimie in French, a study that made a deep impression on him. Two years later he published an essay in which he refuted Lavoisier’s caloric; that same year he established his reputation as a chemist with his book Researches, Chemical and Philosophical, chiefly concerning Nitrous Oxide . . . and its Respiration in which he suggested that nitrous oxide (laughing gas) be used as an anesthetic in minor surgical operations. Davy had arrived at his conclusions after a series of risky experiments with different gases on himself. He described his “emotions” after awakening from the effects of laughing gas as “enthusiastic and sublime.”

Davy engaged in electrochemical experiments that led to several discoveries, including the recognition that the production of electricity was linked to a chemical reaction. He also isolated and analyzed the chemical elements potassium, sodium, magnesium, calcium, strontium, and barium. One of his best-known contributions to the field was his conclusion that, contrary to Lavoisier’s claims, there was no material basis for acidity. In 1810 he announced that the green gas contained in sea salt was an element. He named it chlorine.

As a strong promoter of applied science, Davy also engaged in various practical projects. He researched the chemistry of tanning, promoted improvements to agricultural practices, and developed a miner’s lamp that inhibited the ignition of the methane gas commonly found in mines. Furthermore, Davy was known as an effective lecturer. He made scientific topics accessible to an audience that extended beyond a small circle of fellow scientists.

Davy’s accomplishments were recognized with numerous awards and honors. In 1801 he joined the faculty of the Royal Institution in London. He became a fellow of the Royal Society in 1803, was awarded the Copley medal in 1805, and served as the Society’s president from 1820 to 1827. He was knighted in 1812 and created a baronet in 1818. He was also a founder of the Geological Society of London, the London Zoo and the Athenaeum.

Davy was married to Jane Apreece Kerr, a wealthy and well-connected widow. They did not have children. In 1829, he suffered a stroke while vacationing in Italy. He died a few days later.