NORTH SYDNEY AND SYDNEY MINES, C. B.— DeWOLFE. 299 



stances the contact is an abrupt one. Not far above the base, 

 a few strata of mixed conglomerate and breccia have been found, 

 interbedded with line sandstone. The rocks at this point are 

 very ferruginous, in some spots sending out small streams of 

 rusty water. The pebbles are almost entirely quartz. Sharp 

 angular pieces and rounded pebbles occur together, such as one 

 often finds upon the beaches of to-day. There is usually a sharp 

 line of demarkation between the conglomerates and sandstones, 

 showing that the conditions of deposition changed somewhat 

 abruptly. The mixture of angular and rounded pebbles sug- 

 gests the proximity of a cliff at the time of deposition. 



It is difficult to determine the thickness of the conglomerate, 

 as only parts of the beds are exposed, but the best estimate 

 possible gives thirty feet as the total. 



Coal. — Throughout the whole upper half of the formation 

 coal seams occur, ranging from one-fourth to two inches in 

 thickness. 



About 386 feet below the base of the Coal Measures is a bed 

 of shale, the first encountered in the Millstone Grit. It con- 

 tains both arenaceous and argillaceous varieties, and a thin 

 layer of red marl. The lower shale grades upward into sand- 

 stone, and this again into shale, twenty-five feet thick. At the 

 base of this shale lies the Ingrahani seam of coal, which, 

 however, is not exposed on the sea clifP. I am informed by old 

 residents that this coal measured two feet, and was worked 

 niany years ago for local supply. It has long since been 

 abandoned. A section of the associated beds at this horizon 

 would be as follows, in ascending order: — 



underclay 2 feet. 



coal (Ingraham seam) 2 



arenaceous shale 6 



sandstone 10 



arenaceous shale 15 



argillaceous shale 10 



red marl 3 



coarse gritty sandstone and conglomerate. . 



