KIRKWOOD, Samuel Jordan, senator, born in Harford county, Maryland, 20 December, 1813. His only schooling was received at an academy in Washington, D. C., and ended when he was about fourteen years old. He removed to Ohio in 1835, studied law, and was admitted to the bar in 1843. From 1845 till 1849 he was prosecuting attorney of Rich-land county, and in 1850-'1 was a member of the State constitutional convention. He removed to Iowa in 1855, engaged in milling and farming, and in 1856 served in the state senate. He was elected governor of Iowa in 1859, and re-elected in 1861. He placed in the field nearly or quite fifty regiments of infantry and cavalry, all but the first being enlisted for three years, and throughout the war there was no draft in Iowa, as her quota was always filled by volunteers. He was offered in 1862 the appointment of United States minister to Denmark, and, in the hope of his acceptance, Mr. Lincoln held the appointment open until the expiration of Mr. Kirkwood's term as governor, but he then made his refusal final In 1866 he was elected United States senator as a Republican, to fill the unexpired term of James Harlan. In 1875 he was for a third time governor of the state, and the next year was re-elected United States senator, serving till 1881, when he resigned to enter the cabinet of President Garfield as secretary of the interior. Since 1882 he has held no public office.--His cousin, Daniel, mathematician, born in Bradenbaugh, Maryland, 27 September, 1814, was educated in York county academy, Pennsylvania, and subsequently devoted his life to educational pursuits, becoming principal of Lancaster, Pennsylvania, high school in 1843, and of Pottsville academy in 1848. In 1851 he was made professor of mathematics in Delaware college, and in 1854 elected president of that institution, holding these offices until 1856. He then received the appointment of professor of mathematics in the Indiana university, Bloomington, and ten years later was called to fill a similar chair in Washington and Jefferson college, Pennsylvania In 1867 he was recalled to Indiana, and has since remained in that university. He received the degree of A. M. from Washington college, Pennsylvania, in 1850, and that of LL.D. from the University of Pennsylvania in 1852. Professor Kirk-wood is a member of various scientific societies, and in 1851 was chosen a member of the American philosophical society. His contributions to scientific literature have been large, and include papers that have been published in the proceedings of societies of which he is a member, and in "The Monthly Notices of the Royal Astronomical Society," "The American Journal of Science," " The Sidereal Messenger," and other journals. Among these have been "Analogy between the Periods of Rotation of the Primary Planets" (1849); " Theory of Jupiter's Influence in the Formation of Gaps in the Zone of Minor Planets" (1866); and " Physical Explanation of the Intervals in Saturn's Rings" (1867). He has also published in book-form " Meteoric Astronomy" (Philadelphia, 1867); " Comets and Meteors" (1873); and "The Asteroids or Minor Planets between Mars and Jupiter" (1887).