388 NORTHERN OUTCROP, CUMBERLAND COAL FIELDS—GILPIN. 
Under the influence of a temporary demand for coal in the 
United States, several mines were opened between Maccan and 
the Jogeins ; but they were abandoned as soon as the necessity 
ceased that called therm into operation. 
When, however, the long dreamt of Intercolonial Railway 
was opened through the centre of the field,a fresh and more lasting 
jmpetus was given to the coal trade. A large and flourishing mine 
was opened at Springhill, through the energy of some merchants 
of St. John, who have been well rewarded for their enterprise in 
taking hold of a property which was rejected by the people of 
Halifax. The demand for fuel at the Londonderry iron works 
has led to the opening of another colliery, and other properties 
are being prepared to meet the revival of business in the mineral 
we are now considering. 
In view of this encouraging state of affairs, it may not prove 
uninteresting to you to learn not only what progress in develop- 
ment has been already effected, but to consider what additional 
stores of mineral wealth may be contained in the district treated 
of in this paper. 
The key to the general structure of the Cumberland coal field 
is found at the Joggins, presented in a beautiful and unbroken 
section of the various divisions of the carboniferous system. This 
has been carefully studied and minutely described by Dr. Dawson 
and the late Sir Charles Lyell, and I shall refer to it so far as 
may be necessary to show its bearing on the distribution of the 
productive measures over a district 25 miles in length. On re- 
ferring to Dawson's “ Acadian Geology,” we will find the J ogeins 
coal-measures bounded above (geologically speaking) by a set of 
massive sandstones (the upper coal measures), and below by a 
series of sandstones, grits and conglomerates (the Millstone grit). 
These massive covers, like the pasteboard of the book-binder’s 
art, serve not to hide, but to preserve the material contained be- 
tween them. The following summary, in descending order, will 
show the relative thickness of these great layers of sediments ; 
UPPER COAL MEASURES. 
Wip per partie. pier tede eae eee 650 feet. 
bower? wll) Ao ies See 2 eatlatal ee 160%, = 
—- 2267 feet, 
