Theory of the Origin of Coal. 541 
making this appeal to my countrymen, because I really believe that 
the high class of merit which belongs to the researches of M. Du- 
bois is yet known to very few of them*. 
Under the head of Asia Minor Mr. Murchison refers to the geological re- 
searches of one of the Secretaries of the Society, Mr. W. J. Hamilton, as 
having connected the region described by M. Dubois with the southern 
Mediterranean types; notices, under the head of Zurkey in Europe, Servia, 
§c., the investigations of M. Boué, uniting the distant regions of Asia Minor 
with Western Europe; and he then briefly relates some of the prominent 
results of the researches of M. Sismonda in the Piedmontese Alps. He next 
proceeds to “ Norra American Guotoecy,” in which he alludes to the com- 
munications on that subject contained in Silliman’s American Journal of 
Science; also to the Memoirs of Professor W. R. and D. H. Rogers, and 
to the papers and views of Mr. R. C. Taylor, Mr. Featherstonhaugh, Dr. 
Dale Owen and others; he then proceeds to the 
Theory of the Origin of Coal—American and European Hvi- 
dences compared.—At the last Anniversary we were aware, from the 
independent evidence of Mr. Lyell, that both the bituminous and 
anthracitic coals of Pennsylvania were underlaid by Stigmaria 
Jficoides and fireclay ; and we have now before us the result of the la- 
bours of our associate Mr. Logan in the coal-fields of Pennsylvania 
and Nova Scotia, in examining which his chief object seems to have 
been to ascertain whether the facts relating to the theory of the origin 
of coal, as seen in North America, were analogous to those to which 
he has so successfully directed attention in England. 
Availing himself of the prior researches of the American geolo- 
gist, Professor H. Rogers and his assistant surveyors, who had pre- 
pared the valuable map of Pennsylvania above alluded to, Mr. Logan 
has laid before us a very clear sketch of the general relations of the 
Pennsylvanian carbonaceous deposits, and of their chief convolu- 
tions. Since that time the Governor and legislature of the Canadas 
have wisely selected this well-trained field geologist to execute 
a mineral survey of the whole province; and I am happy to 
acquaint you that he has already commenced his task in a very ef- 
fective and vigorous manner, by laying down as the base-lines of his 
work some of the great anticlinals and synclinals of that region, and 
by connecting them with the already described feature of the 
United States. In comparing the coal-field of Pennsylvania with 
those of South Wales, with which he is familiar, Mr. Logan states, 
that he almost invariably detected beneath each anthracitic coal-seam 
a bed of fireclay or argillaceous materials filled with Stigmaria 
ficoides. n his description of the coal-fields of Nova Scotia, which 
have not yet been fully developed, but among which we hear of one 
bed of clear coal twenty-four feet thick, and affording 250 tons daily, 
Mr. Logan states he had also detected the Stigmaria ficoides in similar 
underclay. With such extended observation spread out before 
them, the evidences in which all seem to point one way, young geo- 
* For the general geological views of M. Dubois, see his letters to 
M. E. de Beaumont, ‘ Bulletin de la Soc. Geol, de France,’ vol. viii. p. 3871 
et seg. His researches have been justly appreciated in France. 
