22 
Proceedings of the Royal Society 
Memoirs in the German Journals, and in the Transactions of the 
Royal Society of Gottingen, and of several separate works on 
Chemistry, Geology, and the Mines of Germany ; but his chief 
productions are his “ Travels in various parts of Scandinavia,” pub- 
lished in five volumes between 1811 and 1818, and his “Manual of 
Mineralogy,” published in 1813, and reprinted in 1828 and 1847. 
Henry Darwin Rogers, LL.D., F.R.S., and F.G.S., a distin- 
guished American Geologist, Professor of Geology in the University 
of Glasgow, and one of the Foreign Members of this Society, was 
born in Philadelphia on the 1st of August 1808, and was the third 
of four brothers, all of whom have been devoted to the cultivation 
and teaching of Physical Science, their father Dr Patrick Kerr 
Rogers, having himself been Professor of Natural Philosophy and 
Chemistry in the College of “ William and Mary ” in Virginia. 
At the early age of twenty-two he was elected Professor of Natural 
History and Physics in Dickinson College, Carlisle, but being 
desirous of improvement, he resigned his chair, and spent above a year 
in England, where he studied Analytical Chemistry in the laboratory 
of Dr Edward Turner, and had the privilege of accompanying Sir 
Henry De la Beche in his geological excursions. 
On his return to Philadelphia he was appointed to the chair of 
Geology in the University of that city, and while discharging its 
duties, which he did for many years, he carried on many important 
scientific researches. Along with Professor A. D. Bache, he made 
an extensive series of Experiments on the Ashes of Coal, and in 
conjunction with his brother W. B. Rogers, he made experiments 
on “ The Laws of the Elementary Voltaic Battery.” 
The first fruits of his geological labours was his Report of the 
Survey of the state of New Jersey, which he published in 1835 
with a large geological map. While engaged in that survey 
he was employed by the legislature to make a survey of the 
great state of Pennsylvania, and to this herculean task he de- 
voted many years of his life. It commenced in 1836, and 
with the aid of a staff of able coadjutors, it was completed in 
1855, and published in three volumes, under the title of “ The 
Geology of Pennsylvania, a Government Survey, with a General 
Survey of the Geology of the United States, Essay on the Coal 
