BENJAMIN SILLIMAN, THE ELDER. 



He was accustomed to explain the success of his lectures, 

 and the uninterrupted interest they attracted, by stating that 

 he always prepared them " with all possible care, and arranged 

 every experiment and illustration so as to insure success. 

 Then I could stand before the largest audience without anxiety 

 or embarrassment ; could, without manuscript, clearly state 

 and explain my subject, and, when the proof became necessary, 

 I could perform the experiments successfully and even beau- 

 tifully, and exhibit the specimens which some other truth de- 

 manded, to insure conviction." 



In 1830 Prof. Silliman made a visit of exploration to the 

 valley of Wyoming, in Pennsylvania, and its coal formations, 

 where he examined some hundred mines and localities of coal, 

 extending through forty miles in length; in i832-*33 he was 

 engaged, under a commission from the General Government, 

 in a scientific examination on the subject of the culture and 

 manufacture of sugar; and in 1836 he made a tour of investi- 

 gation among the gold mines of Virginia. 



In 1840 an association of geologists was formed in Phila- 

 delphia for the purpose of promoting the progress of their 

 science and its applications in this country, and Prof. Silli- 

 man was chosen its first president. This society was in time 

 succeeded by the " American Association of Geologists and 

 Naturalists," and the latter eventually became the "American 

 Association for the Advancement of Science." 



In 1849 Prof. Silliman, having reached the age of seventy 

 years, tendered a resignation of his professorship, to take 

 effect at the end of the ensuing academic year. The corpora- 

 tion, only half accepting his resignation, requested him to con- 

 tinue his lectures in the department of mineralogy and geol- 

 ogy, should his life and health be spared. Later, at the re- 

 quest of the corporation, he reconsidered his resignation, and 

 continued in the full occupation of his professorship till 1853, 

 when, " wishing to go out before he should be compelled by 

 infirmity, and to march out of the camp with colours flying," 

 he retired finally. " Thus," he remarks in his journal, after re- 

 ferring to the public notices that were taken of his retirement 

 during commencement week, " I have finished my regular con- 

 nection with Yale College, after having been almost fifty-four 

 years an officer of the institution three years a tutor, fifty- 

 one a professor, and almost fifty a lecturer. ... I seem to 



