_Silliman’s Students and Their Publications._—Silliman’s first student to take up geology as a profession was Denison Olmstead (1791–1859), educator, chemist, and geologist, who was graduated from Yale in 1813. Four years later he was under special preparation with Silliman in mineralogy and geology, and in that year was appointed professor of chemistry in the University of North Carolina. In 1824–1825 Olmstead issued a Report on the Geology of North Carolina, which is the first official geological report issued by any state in America, “a conspicuous and solitary instance,” according to Hitchcock’s review of it (=14=, 230, 1828), “in which any of our state governments have undertaken thoroughly to develop their mineral resources.” Amos Eaton (1776–1842), lawyer, botanist, surveyor, and one of the founders of American geology, was a graduate of Williams College in the class of 1799. He studied with Silliman in 1815, attending his lectures on chemistry, geology, and mineralogy. He also enjoyed access to the libraries of Silliman and of the botanist, Levi Ives, in which works on botany and materia medica were prominent, and was a diligent student of the College cabinet of minerals. He settled as a lawyer and land agent in Catskill, New York, and here in 1810 he gave a popular course of lectures on botany, believed to have been the first attempted in the United States. In 1818 appeared Eaton’s first noteworthy geological publication, the Index to the Geology of the Northern States, a text-book for the classes in geology at Williamstown. The controlling principle of this book was Wernerism, a false doctrine from which Eaton was never able to free himself. This book was “written over anew” and published in 1820. While at Albany in 1818, Governor De Witt Clinton asked Eaton to deliver a course of lectures on chemistry and geology before the members of the legislature of New York. It is believed that Eaton is the only American having this distinction, and because of it he became acquainted with many leading men of the state, interesting them in geology and its application to agriculture by means of surveys. In this way was sown the idea which eventually was to fructify in that great official work: The Natural History of New York. (See =43=, 215, 1842; and Youmans’ sketch of Eaton’s life, Pop. Sci. Monthly, Nov. 1890.) Edward Hitchcock (1793–1864), reverend, state geologist, college president, and another of the founders of American geology, was largely self-taught. Previous to 1825, when he entered the theological department of Yale College, he had met Amos Eaton, who interested him in botany and mineralogy, and between 1815 and 1819 he had made lists of the plants and minerals found about his native town, Deerfield, Massachusetts. Therefore, while studying theology at Yale it was natural for him also to take up mineralogy and geology with Silliman, whose acquaintance he had made at least as early as 1818.