Alexander Dallas Bache, an American savant and hvdrographer, born in Philadelphia, July 19, 1806, died in Newport, R. I., Feb. 17, 1867. He was the son of Richard Bache and Sophia Burnet Dallas, and a great-grandson of Benjamin Franklin. He attended a classical school in Philadelphia, and in his 15th year was appointed a cadet at West Point, where he graduated with high honors in 1825, becoming a lieutenant of engineers. He was retained for some time at the academy as an assistant professor, and subsequently served two years under Col. Totten in engineering work at Newport, R. I., where he formed the acquaintance of Miss Nancy Clarke Fowler, afterward his wife and his collaborator in astronomical observations. He next filled the chair of natural philosophy and chemistry in the university of Pennsylvania at Philadelphia, and became a member of the newly established Franklin institute.

A full account of his arduous labors in that period for the promotion of mechanical arts is contained in the "Journal" of the institute for 1828-'35. He was associated with Hare, Espy, and other learned men in the American philosophical society, and built a private observatory, where with his assistants he determined, for the first time in the United States, the periods of the daily variations of the magnetic needle, and made other novel and interesting observations. In 1836 he was chosen president of the board of trustees of Girard college, preparatory to organizing that institution, and went to Europe to examine the educational systems of England, France, Prussia, Austria, Switzerland, and Italy. On his return in 1838 he submitted to the trustees a full report, which contributed much to improve the American methods of public instruction. Owing to delays in the opening of the college, he relinquished his salary as president, though retaining this title till 1842. In the meanwhile he organized a system of free education in Philadelphia, at first gratuitously, and subsequently receiving a salary from the city authorities.

While engaged in this work he also cooperated with the British association in the determination by contemporaneous observations of the fluctuations of magnetic and meteorological phenomena. In 1842, having completed the organization of the schools, which served as models for many similar institutions, he resumed his former chair in the university. In November, 1843, he was appointed superintendent of the United States coast survey as successor of Mr. Hass-ler. To this work he imparted a value and efficiency such as it had never possessed before. He was also superintendent of weights and measures, lighthouse commissioner, and afterward member of the lighthouse board, regent of the Smithsonian institution, and a vice president of the United States sanitary commission. The degree of LL. D. was conferred upon him by various universities, and he received medals from foreign governments and institutions. He was successively president of the American philosophical society, of the American association for the advancement of science, and of the national academy of sciences, the establishment of the last two societies having been chiefly promoted by his influence, and he was associated with almost all distinguished scientific bodies in both hemispheres.

He bequeathed about $42,000 to the national academy of sciences for the prosecution-of researches in physical and natural science, by assisting experimenters and observers in such manner as shall be agreed upon by Professors Henry, Agassiz, and Peirce, or their successors, or by any two of them, these three trustees to constitute a board for the selection of scientific subjects, and for the publication of the observations and experiments, the expense to be defrayed out of the annual income accruing from the legacy, without encroaching on the capital.

Among his works are: "Observations at the Magnetic and Meteorological Observatory at the Girard College" (3 vols., 1840-'47); his annual reports on the coast survey and on weights and measures; numerous contributions to periodical publications of scientific societies, including many valuable essays in the "Proceedings of the American Association for the Advancement of Science" (1829-65); and "Lecture on Switzerland," published from his MS. in the report of the Smithsonian institution for 1870.

BA€HE, Benjamin Franklin, an American physician, great-grandson of Benjamin Franklin, born in Monticello, Va., Feb. 7, 1801.. He graduated at Princeton college in 1819, and at the medical department of the university of Pennsylvania in 1823; entered the navy as assistant surgeon in 1824, and in 1828 was promoted to be surgeon. While on furlough, from 1838 to 1841, he occupied the professorship of natural sciences and natural religion in Kenyon college, Ohio. He served as fleet surgeon of the Mediterranean squadron 1841-'4, and of the Brazil squadron 1848-50. He organized and perfected the laboratory at New York whence are supplied all the appurtenances of the medical department, and of which he was director from 1855 to 1871. At the beginning of the civil war in 1861 he rendered important service to the government by rapidly restocking the laboratory on his own responsibility. He was placed on the retired list in 1863, and in 1871 was promoted to be medical director with the relative rank of commodore.