Description

Paris, J. [L.] Boilly, 1823. Engraved broadsheet (36.3 x 27.3 cm). = A rarely-seen portrait of the French physicist and chemist Pierre Louis Dulong FRS (1785-1838). "He is remembered today largely for the law of Dulong and Petit, although he was much-lauded by his contemporaries for his studies into the elasticity of steam, conduction of heat, and specific heats of gases. He worked most extensively on the specific heat capacity and the expansion and refractive indices of gases. He collaborated several times with fellow scientist Alexis Petit, the co-creator of the Dulong-Petit law. Dulong also discovered the dangerously sensitive nitrogen trichloride in 1811, losing three fingers and an eye in the process. The fact that Dulong kept the accident a secret meant that Humphry Davy's investigation of the compound had the same unfortunate consequence, although Davy's injuries were less severe. "In addition to his accomplishments in chemistry, Dulong has been hailed as an interdisciplinary expert. His contemporaries in the Royal Society of London acknowledged his 'command of almost every department of physical science'. In 1815, Dulong collaborated for the first time with Alexis Petit, in publishing a paper on heat expansion. The two would continue to collaborate, researching the specific heats of metals. In 1819, Dulong and Petit showed that the mass heat capacity of metallic elements are inversely proportional to their atomic masses, this being now known as the Dulong-Petit law. This law, though largely discredited in modern times, helped develop the periodic table and, more broadly, the examination of atomic masses" (Wikipedia). The artist, Julien-Léopold Boilly (1796-1874) was noted for his album of lithographs, Iconographie de l'Institut royal de France ou collection des portraits des Membres composant les quatre académies depuis 1814 jusqu'en 1825 (1820-1825). His portraits are much less stiff and formal than many by his contemporaries. Signed by the artist in the lower left margin of the portrait. The caption states the date of his birth and the year (1823) when Dulong was elected as a member of the Institut. Uncut. With in the upper left margin a rather vague damp-stain; scattered foxing throughout, some marginal creasing, and in lower right corner a small, oval blindstamp, 'Galerie Vivienne Bénard'. Some light creasing and denting in the right margin; otherwise very good.