Page:Popular Science Monthly Volume 30.djvu/717

 Rh intelligible and attractive to the unscientific, and was an impressive public speaker. His first course of lectures was on “The Chemical Relations of the Living World to the Atmosphere,” and dealt with the geological history of the earth and with those large generalizations concerning the respiration of plants and animals that were shown to depend ultimately upon the forces of the sunbeam. These lectures were early examples of his fondness for broad scientific conceptions that bring together all departments of Nature, and his later lectures upon the “Chemistry of the Sunbeam,” the “Dynamics of Life,” etc., by which he was at one time widely known as a popular teacher of science, are also illustrations of this mental tendency.

The “Hand-Book of Household Science,” published in 1857, was designed as a text-book for girls, and is another illustration of my brother's passion for applied science. He believed that the bearings of science upon the economy of the household was “first in the order of importance among things to be considered by rational and civilized people”; and that “it is the duty of popular education to communicate that information which can be reduced to daily practice and yield the largest amount of positive good.” The book was a most painstaking labor, and is a mine of useful knowledge concerning matters of constant interest to everybody.

Professor Youmans was married in 1861 to Mrs. William L. Lee, the widow of a distinguished lawyer and jurist, and a lady of culture, refinement, and much critical literary ability. That a wife of such nice perceptions and intellectual gifts should earnestly sympathize with the literary and scientific work of her husband was to be expected. As his amanuensis, and as an assistant and companion in the occupations, correspondence, and travel, by means of which he was brought into intimate relations with the leading thinkers of England and America, she rendered him valuable aid which he highly appreciated.

“The Correlation and Conservation of Forces” (1864) is a collection of essays and addresses by the most eminent leaders of science concerning the new theory of the relations of forces, with an introduction by the compiler, prepared in order to bring forward certain facts in the history of discovery concerning the correlation and conservation of forces in which we as Americans have a special interest; and also to indicate several applications of the principles not treated in the body of the volume. At one time my brother was strongly urged to take the presidency of Antioch College. He did not entertain this proposal, but when asked to take the chair of Chemistry in that institution as non-resident professor, he accepted the appointment provisionally, and gave a course of lectures there in 1866. Various circumstances, however, made it impossible to continue the arrangement.

“The Culture demanded by Modern Life” (1867) presented a