1862.] 103 [I^esley. 



The Albert or Pictou section is said also to contain but 6ve or sis 

 seams of coal, two of which are of unusual thickness, as follows : 

 From the surface, down the Success Pit, 7o feet; Main Coal, 39.11 

 feet thick; Interval, 157 feet; Deep Seam, 24.9. Both these coal- 

 beds, however, are far from presenting solid faces of coal. On the 

 contrary, they are built up, like the oO and 60 foot coal-beds of the 

 Anthracite region of Pennsylvania, of many layers separated by under- 

 minings. The peculiarity here is that these separations are plates of 

 ironstone, not more than six inches thick, instead of being layers of 

 fire-clay, coal-slate, or sandstone. The structure is certainly peculiar, 

 and evinces quietness of deposit and long-continued stability of sea- 

 level, unless we prefer to consider the Pictou area as an upland 

 swamp, unaffected by certain changes of relative land and sea level 

 then going on and affecting the swamps of the coal era around and 

 below it. 



But inasmuch as the 60 foot coal at Mauch Chunk, on the Lehigh, 

 is identifiable with the Low Main or Mammoth bed of the Pottsville 

 Basin to the west, and of the Beaver Meadow, Hazleton, Buck 

 Mountain, and Wyoming Basins to the north of it, and through them 

 with still smaller and separated beds further off in the Mahanoy and 

 Shamokin Basins, and even with the bituminous basins of the Alle- 

 ghany Mountains, — there can be no reasonable doubt, a priori, that 

 the 25 and 40 foot beds of Pictou are identifiable with 5 and 6 foot 

 beds of New Brunswick on the one side, and with the 8 and 9 foot 

 beds of Sydney on the other,* The palaeontological unity of the 

 Low Main coal of the Pittsburg region with the Low Main coal of 

 Eastern Pennsylvania admits of no doubt. The structural evidence 

 is coincident and precise. Yet, wider intervals of Devonian and Si- 

 lurian denudation are to be bridged by the theoretical connection 



* To illustrate in a still more striking manner this separation of a large bed 

 into several smaller ones, one has only to examine Mr. Jukeis's description of the 

 Thick Coal of Dudley, in England, "which, forming at that place o)te solid seam 

 ten yards in thickness, becomes split up into itine distinct seams by the intercala- 

 tion of 420 feet of strata over the northern area of the coal-field." The Main 

 Coal of the Warwickshire area is split up, according to Mr. Howell, mio fii-c beds 

 by 120 feet of intervening strata. The Main Coal of Moira is noticed by Mr. Hull 

 as a third instance. (See Hull's Paper on the Carboniferous Strata of England, 

 Vol. XVIII, No. 70, Quar. Jour. Geol. Soc. p. 1.39.) Mr. Lesquereux, in his 

 Report on the East Kentucky Conl-Field, in the fourth volume of Owen's State 

 Reiwrts, p. 360, gives what he considers sufficient evidence of a similar breaking 

 up of the Low Main Coal of the Pittsburg area into three. This is precisely the 

 normal number of large beds into which the great Mauch Chunk or Mammoth 

 Bed separates throughout the Pottsville-Tamaqua Basin. 



