576 REPORT OF NATIONAL MUSEUM, 1904. 



filled with bituminous matter. The source of the bituminous matter 

 he supposed to be the Lower Carboniferous shales. In his own words: 



The deposit of the Albert mine would thus be a vein or fissure constituting an 

 ancient reservoir of petroleum which, by the loss of its more volatile parts and partial 

 oxidation, has been hardened into a coaly substance. 



He regarded the Nova Scotia gypsum beds as due to the alteration of 

 beds of limestone by free sulphuric acid poured into the sea by springs 

 or .streams issuing from the volcanic rocks. In this connection he 

 gave a highly interesting verbal picture of the condition of affairs, as 

 he imagined them to exist, at what is now the Southern Hants and 

 Colchester at the time when the marine limestones and gypsums were 

 produced. 



At this period, then, all the space between the Cobequids and the Rawdon Hills 

 was an open arm of the sea, communicating with the ocean both on the east and 

 west. Along the margin of this sea there were in some places stony beaches, in 

 others low alluvial flats covered with the vegetation characteristic of the Carboniferous 

 period. In other places there were creeks and lagoons swarming with fish. In the 

 bottom, at a moderate distance from the shore, began wide banks of shells and corals, 

 and in the central or deeper parts of the area there were beds of calcareous mud with 

 comparatively few of these living creatures. In the hills around, volcanoes of far 

 greater antiquity than those whose products we considered in a former chapter, were 

 altering and calcining the slaty and quartzose rocks; and from their sides every land- 

 flood poured down streams of red sand and mud, while in many places rills and 

 springs, strongly impregnated with sulphuric acid, were ii< >wing or rising, and entering 

 the sea, decomposed vast quantities of the carbonate of lime accumulated by shells 

 and corals and converted it into snowy gypsum. 



The fauna of the seas of the Lower Carboniferous coal formations 

 and Permian periods, both in Europe and America, presented so great 

 similarities that, in a broad view, he felt they were identical. The 

 changes and the subdivisions of this fauna were related not merely to 

 lapse of time but to vicissitudes of physical conditions. It followed 

 that, according to his reasoning, if the peculiar Permian conditions 

 indicated by the rocks came earlier in Nova Scotia than in Europe the 

 character of the fauna might also be changed earlier. In other words, 

 "We have both rocks and shells with Permian aspect in the earlier 

 Carboniferous period." The fact that the marine fauna of the Lower 

 Carboniferous of Nova Scotia more nearly resembled that of Europe 

 than the western States he regarded as indicating that the Atlantic was 

 at that time probably an unobstructed sea basin as now, while the Appa- 

 lachians already, in part, separated the deep-sea fauna of the Carbon- 

 iferous seas east and west of them. 



Concerning the origin of coal he wrote: "Mineral charcoal results 

 from subaerial decay; the compact coal, from subaqueous putrefaction 

 more or less modified by heat and exposure to air. " Further, he regarded 

 mineral charcoal as the wood}^ debris of trees, while the compact coal 

 was produced from the bark of these same trees along with such woody 



