Gerard Troost — Glenn. ' 75 
found at cape Sable on the ^lagothy river in Maryland, 
thus estabhshing the first alum manufactory in the United 
States. He later removed there from Philadelphia, but after 
a few years the failure of the proprietors involved him in 
heavy financial loss, the works were closed, and he returned 
to Philadelphia. In 1821 he was appointed professor of min- 
eralogy in the Philadelphia museum and delivered a course 
of public lectures on the subject. At about the same time he 
was also appointed first professor of chemistry in the Phila- 
delphia College of Pharmacy. He delivered one course of 
lectures and resigned the following year. During this last 
residence in Philadelphia he made frequent geological excur- 
sions into the region around Philadelphia, to the zinc mines 
of Sussex County, N. J., and to Orange County, N. Y., and 
elsewhere, being accompanied at times by Maclure, Say, Le- 
sueur, and Jackson. 
Between 1821 and 1825 he made for the Philadelphia 
Society for the Promoting of Agriculture a geological sur- 
vey of the environs of Philadelphia. 
In 1825, along with Alaclure, Say, Lesueur and others, he 
removed to New Harmony, Indiana, and aided in forming the 
communistic colony there under the auspices of Robert 
Owen. He soon becam.e dissatisfied with the impracticable 
schemes and peculiar social arrangements of Owen, and re- 
moved with his family and scientific collections to Nashville, 
Tenn. During his stay at New Harmony, however, he made 
a trip into southeast Missouri along with Lesueur to the lead 
and zinc mines of that state. He called the attention of the 
miners there to the true nature of the calamine ore, all of 
which they had previously thrown away as worthless. 
It is very probable that Dr. Troost was induced to move 
to Nashville by Dr. Philip Lindsley, the president of the 
University of Nashville. On January 11, 1828, he adver- 
tised in one of the daily papers that his museum, the work 
of twenty years collecting, is now open to the public, and 
mentions tHat among its contents are over 400 species of 
birds from the island of Java alone. — one of the results, no 
doubt, of the interest in Java aroused by his attempted ex- 
pedition to that island. On February 9, 1828, he was elected 
professor of geology and mineralogy in the Universitv of 
