American Association for the Advancement of Science, held at St. Louis. He was there elected President of the Association for the next meeting, to be held at Saratoga, August 27, 1879.
Professor Barker has well earned his distinctions, but he is to be congratulated on having also obtained them. He has been the recipient of many deserved honors, and now, in middle life, after a twenty years' membership, he is called upon to preside over the deliberations of the largest scientific body in the country, and to fill the chair that has been occupied by all of our ablest scientific men.
Professor Barker manifested at a very early age a taste for the sciences which he has subsequently cultivated so successfully. While yet a boy he was intrusted with the apparatus belonging to the academies where he was at school, and converted his sleeping-room into a chemical laboratory. As an apprentice he extended his acquaintance with instrumental appliances, and constructed for himself in his leisure hours a very complete set of electrical and pneumatic apparatus. The familiarity with the use of tools, and the knowledge of the construction of instruments thus acquired, have no doubt been of the greatest practical benefit to him in subsequent life. Indeed, it is said that, when he went to Pittsburg as professor, much of the apparatus placed in his hands for purposes of instruction was the identical apparatus which he had made in Boston as an apprentice ten or twelve years before. Though upon his graduation from Yale he made chemistry his profession, turning his attention more particularly to its physiological relations after taking his doctor's degree, he yet kept up his interest in physics, especially in the departments of electricity and spectroscopy, until upon his removal to Philadelphia he made physics the subject of his instructions, though still keeping up his knowledge of chemistry.
Professor Barker's reputation as a chemist rests chiefly upon his work in chemical theory, he having been among the first in this country to appreciate the advantages of the new views, to use them in his own work, and to teach them to his students. In physics his spectroscopic work upon the metals, upon auroras, and upon the phenomena of solar eclipses has been of high scientific value. But it is as an instructor in science that the chief part of his time has been spent. Not only in the class-room and the laboratory with his students, but also in the public lecture-room, and before the largest audiences, has his power of elucidation and illustration gained for him preeminence. He has served as scientific expert in a number of noted patent cases. He has acted as one of the chemical editors of the "American Journal of Science and Arts" since July, 1877, having prepared the abstracts of chemical papers which were published in that Journal since 1868. He was editor of the "Journal of the Franklin Institute" during 1874-'75; and he prepared, at the request of Professor Baird, the chemical and physical notes for the "Scientific Rec-
