696 THE POPULAR SCIENCE MONTHLY. 



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 recipi- 

 ent 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 acad- 

 emies 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 construc- 

 tion 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 physiologi- 

 cal relations after taking his doctor's degree, he yet kept up his inter- 

 est in physics, especially in the departments of electricity and spectro- 

 scopy, 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 phe- 

 nomena 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 stu- 

 dents, but also in the public lecture-room, and before the largest audi- 

 ences, 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 Frank- 

 lin Institute " during 1874-'75 ; and he prepared, at the request of Pro- 

 fessor Baird, the chemical and physical notes for the " Scientific Rec- 



