Nathaniel Bowditch (1773–1838) was a pioneer in the study of astronomy and mathematics in America. At first a cooper and then a ship-chandler, he was studious, and learned Latin in order to read Newton’s “Principia.” As supercargo on a merchant vessel during several voyages, he became expert in the theory of navigation and published in 1802 “The New American Practical Navigator,” which in a revised form is published by the United States Hydrographic Office and is the standard compendium for navigators. In 1829 he translated Laplace’s “Méchanique céleste,” adding valuable notes.

Benjamin Peirce.—In the annals of mathematics and astronomy the name of Benjamin Peirce (1809–1880) has a place of distinction. Born at Salem, Massachusetts, he became a pupil of Bowditch, and graduated at Harvard in 1829, in the class with Holmes. He became a tutor at Harvard in 1831, professor of mathematics and physics in 1833, and nine years later Perkins professor of mathematics and astronomy, holding this chair till his death. From 1867 till 1874, succeeding Dallas Bache, he was superintendent of the Coast Survey. He wrote an important series of mathematical text-books; “System of Analytical Mechanics” (1857); “Linear Associative Algebra” (communications to the National Academy of Sciences, collected in 1870); and Lowell Institute lectures on “Ideality in the Physical Sciences” (1881). He obtained eminence, it has been said, equally in mathematics, physics, astronomy, mechanics, and navigation.

The Sillimans.—In the annals of American science no other name is so long and favourably known as that of the Sillimans. Benjamin Silliman (1779–1864) was for fifty years, beginning in 1802, professor of chemistry in Yale College and founded (1818) The American Journal of Science and Arts, which he edited for twenty-eight years. His son, Benjamin, Jr. (1816–1885), taught and studied chemistry, mineralogy, and geology in Yale, and was associate editor (1838–1846) of his father’s Journal. For the rest of his life he was a professor of chemistry, first in what is now the Sheffield Scientific School of Yale, then at Louisville University, and later in the Academic and Medical Departments at Yale. In 1858 he published “First Principles of Natural Philosophy or Physics”; and he was the author of many scientific memoirs, addresses, and reports. He was one of the pioneers in science-teaching in America, and his influence on scientific education was deep and abiding.

Joseph Henry.—Joseph Henry (1797–1878) was one of the most illustrious physicists of his day. Born and educated at Albany, New York, he began (1827) researches which resulted in important discoveries in the field of electro-magnetism, one of which made the telegraph possible. From 1832 till 1846 he was professor of natural philosophy in the College of New Jersey (Princeton), and from 1846 till his death was secretary of the Smithsonian Institution, which he had helped to organise. He published “Contributions to Electricity and Magnetism” (1839) and many papers, especially in the Smithsonian reports. A brilliant and profound investigator, he did signally important service in organising great scientific enterprises. “To Henry,” says Dr. Woodward, “more than to any other man, must be attributed the rise and the growth in America of the present public appreciation of the scientific work carried on by governmental aid.”

Alexander Dallas Bache.—Alexander Dallas Bache (1806–1867), a great-grandson of Benjamin Franklin, after graduating in 1825 at West Point, at the head of his class, at twenty-two resigned a lieutenant’s commission to become professor of natural philosophy and chemistry at the University of Pennsylvania. Having made a name for his researches on steam, magnetism, etc., he was called in 1843 to be superintendent of the United States Coast Survey, and performed his duties with marked efficiency. Gifted with quick apprehension and broad intelligence, he possessed great powers of leadership. He published nearly two hundred scientific papers, memoirs, and reports. “To him,” declared his eulogist Benjamin Gould, “the scientific progress of the nation was indebted more than to any other man who had trod her soil.”

Matthew Fontaine Maury.—Matthew F. Maury (1806–1873) is well known to students of meteorological science and also to the educational world. He was a Virginian of Huguenot extraction, who went to sea at nineteen and became not only a good sailor but also an authority on navigation. His “Treatise on Navigation” (1835) was favourably received abroad and was used as a text-book in the United States Navy. As “Harry Bluff” he published in The Southern Literary Messenger, about 1840, under the title of “Scraps from the Lucky-Bag,” a series of papers on nautical matters, which brought him fame and resulted in placing him in charge of the Depot of Charts and Instruments at Washington, an office which later became the Naval Observatory and Hydrographical Department. One of his first tasks was to compile some charts of winds and currents. These charts proved immensely valuable by shortening voyages and lowering the expense of commerce. His “Physical Geography of the Sea and its Meteorology” (1855) at once took the highest rank in its field, and the geographical text-books which he wrote in his later years have done great service to education and in a revised form still satisfy the needs of many schools. He was the author also of many pamphlets and official papers.

Josiah Parsons Cooke.—Josiah Parsons Cooke (1827–1894), a pioneer in chemical education, was born in Boston and graduated at Harvard in 1844. In 1851 he became professor of chemistry and mineralogy at Harvard. He did much to further the study of chemistry in colleges and was one of the first to urge the laboratory method of instruction. He published, among other things, “Chemical Problems and Reactions” (1853), “Religion and Chemistry” (1864), “The New Chemistry” (1871), and “The Credentials of Science the Warrant of Faith” (1888).

John William Draper.—John W. Draper (1811–1882) is known in the annals of science as a chemist and physiologist; he won eminence also as a historian. Born at St. Helens, near Liverpool, the son of a Wesleyan Methodist minister, he studied chemistry under Turner in London, and coming to America in 1833, graduated in medicine from the University of Pennsylvania in 1836. He now began investigating the chemical action of light, and published in 1844 a “Treatise on the Forces which Produce the Organisation of Plants.” His memoir “On the Production of Light by Heat” (1847), a valuable contribution to the subject of spectrum analysis, appeared thirteen years before Kirchoff’s celebrated memoir, which used to be thought of as marking the beginning of spectrum analysis. He was also the first to succeed (1839) in taking portraits of the human face by photography. In 1839 he became professor of chemistry, and in 1850 of physiology also, in the University of New York. His “Treatise on Human Physiology, Statical and Dynamical” (1856) at once took its place as a standard text-book. He wrote also a “Text-Book on Chemistry” (1846); a “Text-Book on Natural Philosophy” (1847); “History of the Conflict between Religion and Science” (1874), an able and comprehensive treatment of a vast subject; and “Scientific Memoirs” (1878), a collection of papers on radiant energy. Two of his sons, Henry and John Christopher, also became well known physiologists and chemists.

Charles Augustus Young.—Of the more recent astronomers of America, Charles A. Young (1834–1908) was one of the foremost. Born in Hanover, New Hampshire, the son of Professor Ira Young of Dartmouth College, he graduated from Dartmouth in 1853. From 1856 till 1866 he was professor of mathematics, astronomy, and natural philosophy in Western Reserve University. In the latter year he returned to Dartmouth as professor of natural philosophy and astronomy, remaining there till 1877, when he became professor of astronomy at Princeton. He was prominently connected with several important astronomical expeditions and produced some notable inventions, among them an automatic spectroscope which has been widely used by astronomers. He made some significant observations on the sun, including a verification by experiment of Doppler’s principle as applied to light, by which he was able to measure the velocity of the sun’s rotation. He also discovered the thin solar shell of gaseous matter called “the reversing layer.” He wrote “The Sun” in “The International Scientific Series” (1882), “A General Astronomy” (1889), “Elements of Astronomy” (1890), and “A Manual of Astronomy” (1902).