COOKE, Josiah Parsons, chemist, born in Boston, Massachusetts, 12 October, 1827. He received his early education at the Boston Latin-school, and was graduated at Harvard in 1848. During the following year he became tutor in mathematics, subsequently instructor in chemistry, and in 1850 Erving professor of chemistry and mineralogy. Under his direction the course in chemistry has been developed from a very small beginning until facilities are afforded for study and investigation not excelled elsewhere. Prof. Cooke was the first to introduce laboratory instruction into the undergraduate course of an American College; and has successfully labored to render the inductive methods of experimental science a legitimate means of liberal culture not only in the College but also in the preparatory school. Prof. Cooke's work has been largely that of instructing, and, in addition to his duties at Harvard, he has given courses of popular lectures in Baltimore, Brooklyn, Lowell, Washington, and Worcester, besides five courses at the Lowell institute in Boston. As director of the chemical laboratory of Harvard College, he has published numerous contributions to chemical science, most of which have been collected in a volume entitled "Chemical and Physical Researches" (1881), which includes much of his scientitle work. The investigation on the atomic weight of antimony (1880) was one of the most brilliant and perfect pieces of chemical work ever executed in this country. It received the commendation of chemists both in the United States and Europe, and its results have been accepted. His numerous mineral analyses, with descriptions of new species, have appeared in the "American Journal of Sciences" and in the "Proceedings of the American Academy of Sciences and Arts," with both of which journals he has been editorially connected. His "New Chemistry" was the earliest exposition of a consistent system of chemistry based on the principles of molecular mechanics. Its philosophy has been widely accepted both in England and in Germany, and the book has been translated into most of the languages of Europe. Prof. Cooke is a member of many scientific societies. In 1872 he was elected to the National academy of sciences, and he is also an honorary fellow of the London chemical society, a distinction which, in this country, is shared with but one other. In 1882 he received the degree of LL.D. from the University of Cambridge, England. His published works are of two kinds. The scientific includes "Chemical Problems and Reactions" (Cambridge, 1857);" Elements of Chemical Physics" (Boston, 1860); "First Principles of Chemical Philosophy" (1868 ; revised ed., 1882); and The New Chemistry" (New York, 1872; revised ed., 1884); "Fundamental Principles of Chemistry" (Cambridge, 1886). The literary comprise "Religion and Chemistry" (New York, 1864) and "Scientitle Culture and other Essays " (New York, 1881 ; with additions, 1885).