I2 2 PIONEERS OF SCIENCE IN AMERICA. 



members came foward with their gifts to serve as the nucleus 

 of the museum and library. Among them was Dr. Troost, 

 with some artificial crystals, prepared by himself. On the oc- 

 casion of the election of officers, May 7, 1812, Dr. Troost was 

 chosen president. He held this office five years, or till 1817, 

 when he resigned and was succeeded by William Maclure. On 

 the i5th of August, 1812, the collection of minerals previously 

 purchased from Dr. Seybert by Mr. Speakman came formally 

 into the possession of the society, which formed a kind of 

 joint-stock company to pay for it and hold it. Soon after this, 

 Dr. Troost delivered a course of lectures on mineralogy before 

 the academy. 



During his residence in Philadelphia Dr. Troost was en- 

 gaged in manufactures of various kinds. In 1815 or 1816 he 

 began the manufacture of alum on the Magothy River, Cape 

 Sable, Maryland, establishing the first alum works in the 

 United States. Owing to the failure of the proprietors, he 

 suffered great pecuniary loss. The War of 1812 with Great 

 Britain had stimulated manufactures, and its termination was 

 disastrous to many enterprising men. In 1821 he was ap- 

 pointed Professor of Mineralogy in the Philadelphia Museum, 

 where he delivered lectures on the subject. He was also ap- 

 pointed about the same time first Professor of Chemistry in 

 the College of Pharmacy, Philadelphia, a position which he 

 resigned, -after having delivered one course of lectures, in the 

 succeeding year. During this period he also made geological 

 excursions into New Jersey, New York, and elsewhere. 



In 1825 Dr. Troost, with Maclure, Say, and Lesueur, joined 

 Robert Owen in the formation of the Communistic Society at 

 New Harmony, Ind. After remaining there two years, he re- 

 moved to Nashville, Tenn., in 1827. In 1828 he was elected, 

 at the instance of President Lindsley, Professor of Chemistry, 

 Geology, and Mineralogy in the University of Nashville. In 

 a historical sketch, published in the catalogue of 1850, is a 

 table of the longest terms of official service of instructors. It 

 is headed by President Lindsley, twenty-six years; and next 

 in length of service comes Prof. Troost, from February 9, 

 1828, to August 14, 1850, twenty-two years and a half. 



In 1831 he was appointed State Geologist of Tennessee, an 

 office which he held till it was abolished in 1839. The record 

 of his work in this department is preserved in his reports. 



