Such is, in short, an account of a practical charity--a charity, in truth, not because something is furnished for nothing, but that so much is given in return for so little. During the past year more than three thousand persons were registered as enjoyers of the privileges offered. Mr. Janssen gave the building and in one sense endowed the work; Mr. Tours gives his time, wisdom, and energy in directing its affairs; they both ask the wiser men and women of the city to give a few hours of each month or year. They have not asked in vain, and the cheerful responses give promise of the coming of the time when the only answer to the question, "Am I my brother's keeper?" will be an energetic "Yes." SKETCH OF FRANK WIGGLESWORTH CLARKE. The great advance which chemical science has made in the United States during the past thirty years has been brought about by the joint operation of several factors, of which we may mention the formation and the influence of chemical societies seeking to further its development, the intelligent labors of individual investigators cultivating special fields, and the systematic pursuit of experimental work with reference to certain definite results. In this shaping of chemical research in such a way as to make it most efficient, the work and influence of Frank Wigglesworth Clarke have been prominent and important. His own labors have been industriously and unselfishly pursued with an eye to the advancement of the science, and their value has been generally recognized. It seems as if he had taken to himself a hint thrown out in one of his earlier scientific papers, and, giving up the transient glory of brilliant experiments, had devoted himself to setting the science as far forward as possible in single branches. Professor CLARKE was born in Boston, March 14, 1847, and was graduated from the Lawrence Scientific School of Harvard University in 1867. Two years later, in 1869, he was appointed instructor in chemistry in Cornell University, the first assistant ever appointed at that institution. His next position was that of professor of chemistry and physics in Howard University, Washington, in 1873 and 1874. In the latter year he became professor of chemistry and physics in the University of Cincinnati, in a position which he held till 1883, when he became chief chemist to the United States Geological Survey and honorary curator of minerals in the United States National Museum, where he still remains.