188 EDWIN GILPIN ON THE FOLDING OF THE 
section, but is probably represented by the basal conglomerates flanking the Cobequid 
Hills. 
At Horton, in Nova Scotia, these measures are met with a thickness apparently some- 
what greater, and having the conglomerates replaced by coarse grits. They can be traced 
to the Shubenacadie River, and on the north shore of the Basin of Minas are represented by 
conglomerates and shales exposed on the shore west of Cape Chignecto, etc. They do not 
appear in Pictou County, except as conglomerates cropping at intervals under the Carboni- 
ferous Limestones, until its eastern boundary is met. In Antigonishe County they follow 
the older hills, chiefly as conglomerates, round to the Lochaber Lake, with a diminishing 
thickness, which appears to increase again until Richmond County is reached. 
Here they are presented with heavy beds of conglomerate, succeeded by dark shales, 
etc. Their thickness is estimated by Mr. Fletcher at 6,000 feet ; it is evident that their 
dimensions here exceed those already noticed, even if they are found, on more extended 
examination, not to reach the figures given above. 
At the base of the Carboniferous in Cape Breton County they are represented by great 
masses of conglomerate, their total thickness varying from 500 to 2,500 feet. Similar con- 
ditions prevail in Newfoundland, where, according to Mr. Murray, their thickness is 1,300 
feet, but the volume may be as variable here as in Cape Breton. 
So far as. our knowledge extends, I believe that these measures pass conformably into 
the succeeding horizon in Newfoundland, Cape Breton, and Antigonishe. Along the 
south side of the Basin of Minas, they, together with the overlying limestones, are 
brought to the surface, along certain lines of great east and west folds, but, so far as I am 
aware, do not show unconformability. In southern New Brunswick the deposition of the 
lower part of these measures appears to have been accompanied by slight oscillations of level 
now marked by unconformable conglomerates. 
The comparatively limited development of these measures along the north side of the 
Cobequids, coupled with their slight development in Pictou County, and at Arisaig, would 
show elevation along this line, accompanied by depression at Hillsboro, and to the south 
at Horton, and similar changes along a line passing from Cape George through the Bras 
d'Or Lake to Cape Breton. 
THE CARBONIFEROUS LIMESTONE. 
This horizon presents itself at numerous points, and in its strongly marked characteris- 
tics, records a state of deposition unlike any other in the area under consideration. Taking 
the districts as they occur, from west to east, we have first to notice its presence as an 
isolated outlier on the Tobique River, where it holds limestone and gypsum, which are of 
interest, being at so great a distance from a corresponding development of these rocks. The 
upper part of this outlier would appear to be continued through the north and north-west 
part of New Brunswick as the Bonaventure formation, attaining in the north a thickness 
of 2,760 feet, according to Sir W. Logan. The characteristics of the formation are revived 
in southern New Brunswick, where it attains a thickness of 3,000 feet, part of which may 
be included in the preceeding horizon. 
At the Joggins this formation attains a thickness of 2,500 feet ; at Springhill, on the 
reverse dip, the thickness must be little less. On the south side of the Basin of Minas 

