Benjamin, an American physicist, born in North Stratford (now Trumbull), Conn., Aug. 8, 1770, died in New Haven, Nov. 24,1864. He graduated at Yale college in 1796, was appointed tutor in 1799, and was admitted to the bar in 1802. He accepted the new chair of chemistry at Yale college in 1802, and passed a part of the next two years in Philadelphia, as a student with Dr. Woodhouse. In the winter of 1805 he gave his first full course of lectures, and shortly after sailed for Europe. He visited the mining districts of England, attended lectures in London and Edinburgh, and resumed the duties of his professorship after an absence of 14 months. He published in 1810 " Journal of Travels in England, Holland, and Scotland in 1805-'6" (2 vols. 8vo; enlarged ed., 3 vols. 12mo, 1820). Not long after his return he made a geological survey of a part of Connecticut. In December, 1807, a meteorite of great size and splendor passed over New England, and threw off large fragments with loud explosions in the town of Western, Conn. Profs. Silliman and Kingsley visited the town and procured some fragments; and Silliman made a chemical analysis and published the earliest and best authenticated account of the fall of a meteorite in America. He afterward assisted Dr. Robert Hare in his experiments with the oxyhydrogen blowpipe, to which he gave the name now commonly used of "compound blowpipe." In 1813 he published in the "Memoirs of (he Connecticut Academy of Arts and Sciences" an account of his experiments with this instrument, byt which he had greatly extended the list of bodies known to be fusible.
In 1812 he secured to Yale college the then unrivalled mineralogical and geological collection made by Col. George Gibbs in Europe. In 1822, while engaged in a series of observations on the action of a powerful voltaic de-flagrator on the model of Dr. Hare, he first established the fact of the transfer of particles of carbon from the positive to the negative electrode of the voltaic apparatus, with the corresponding growth of the negative electrode, and the retransfer when the charcoal points are shifted. In 1818 he founded the "American Journal of Science and Arts," better known both in Europe and America as "Silliman's Journal," of which for 20 years he was sole, and for eight years more senior editor. He was one of the earliest American lecturers on scientific subjects to miscellaneous audiences, and delivered courses in the principal cities. He published an account of a journey between Hartford and Quebec (1820), an edition of BakewelFs " Geology" (1829), and a text book on "Chemistry" (2 vols., 1830). In 1851 he again visited Europe, and published "A Visit to Europe in 1851 " (2 vols. 12mo, New York, 1853). In 1853 he resigned his professorship, and was made professor emeritus; but at the request of his colleagues he continued to lecture on geology till June, 1855. His life has been written by Prof. George P. Fisher (2 vols., New York, 1866).
Jr Benjamin, an American physicist, son of the preceding, born in New Haven, Conn., Dec. 4, 1816. He graduated at Yale college in 1837, became an instructor there in chemistry, mineralogy, and geology, and in 1846 was appointed professor of chemistry applied to the arts in the scientific school of the college, now the Sheffield scien- • tific school. He became associate editor of the "American Journal of Science" in 1838, and since 1854 has been associated with Prof. J. D. Dana as editor and proprietor. From 1849 to 1854 he was professor of medical chemistry and toxicology in the university of Louisville, Ky.; and in 1854 he succeeded his father as professor of general and applied chemistry in Yale college, which post he still holds (1876). In connection with C. R. Goodrich he prepared the "Illustrated Record" and the "Progress of Science and Art" published in connection with the international exhibition of 1853 in New York. He was for several years secretary of the American association for the advancement of science, and had charge of the publication of its "Proceedings." He is also a popular lecturer.
Besides numerous papers in the "American Journal of Science," he has published "First Principles of Chemistry," a popular text book (Philadelphia, 1846; revised ed., 185G), and "Principles of Physics" (Philadelphia, 1858; revised ed., 18G8).