458 T., W. E. DAVID AND E. F. PITTMAN. 
Thickness. Total depth. 
Ft. In. Bt. aie 
Coal seam ... 10 3 2,927 3 
Permo-Carboniferous—Newcastle 
Series. 
Clay shale and 
mindstone with 1 9 225° eo 
Vertebraria. 
The line of division between the Mesozoic and Paleozoic rocks 
has been drawn at the top of the coal seam for the reason that 
the horizon of the ironstone nodules, which is well marked as 
forming the basal bed of the Hawkesbury Series, was found to 
descend at this bore to within a few feet of the coal seam. 
(b) Dip of the Seam.—At the No. 1 Cremorne Bore the surface 
level was fifty-four feet above the sea, and at the No. 2 Bore one 
hundred and forty-three feet above sea-level. At the No. 1 Bore, 
the coal was struck at 2,801 feet 9 inches, and at the No. 2 Bore 
at 2,917 feet. Consequently the seam at the No. 2 Bore was one 
hundred and fifteen feet deeper (in round numbers) than at the 
No. 1 Bore, whereas there was a difference in the surface levels 
of only about eighty-nine feet. The seam has therefore dipped 
from the No. 1 Bore towards the No. 2 Bore twenty-six feet ina 
distance of forty chains in a direction of North 34° West. 
At the Narrabeen Bores the chocolate shales were struck at a 
depth of three hundred and seventy-nine feet six inches, the 
distance from the No. 2 Cremorne Bore being nine and a-half miles 
and the bearing North 5° 45’ Hast. The surface level being about 
four feet above the sea. 
At Holt Sutherland, the surface level being one hundred and 
thirty-two feet above the sea, the depth to the first seam of coal 
was 2,228 feet, and to the second seam 2,2963 feet. If the authors’ 
opinion be right that these two seams come together and become 
united to form the single ten feet three inches seam at Cremorne, 
the depth to the top of the lower seam with the thickness of the 
upper seam subtracted from it should be taken as the level from 
which to measure the dip of the seam from Holt Sutherland towards 
Cremorne, that is 22964 feet — 4 feet 2 inches = 2,292 feet in 
round numbers. The total dip therefore from the Holt Suther- 
land Bore to the No. 2 Bore at Cremorne has been six hundred 
