326 PROCEEDINGS OF SECTION C. 



water gradually rose in the Moonlight shaft, but subsided 

 again as the former mine again became unwatered. 



These instances, and numerous othei's that could be cited, 

 show the great ease with which at the present day water 

 passes through the rocks of this district, and it is reasonable 

 to suppose that in Early Tertiary times it would be similarly 

 easy, and that there would be no great difficulty in the way 

 of very considerable quantities of fine peaty sludge being 

 carried down into the crevices and more broken parts of the 

 ground by water seeking a natural outlet. 



Coming now to the chemical and physical properties of 

 the carbonaceous substance, we find that it comes nearer to 

 lignite or brown coal than to anything else. It is from 

 brownish black to pitch black in colour, soft, pulverulent and 

 earthy to coherent and brightly lustrous, with brownish dark 

 streak, and specific gravity slightly greater than thatjof 

 water. Much of it has a finely banded structure, alternate 

 layers being bright black and brownish earthy, slightly 

 suggesting a woody structure at a first glance. 



The average composition was found by analysis to be as 



follows : — 



Per cent. 



Carbon 38-91 



Hydrogen 3"03 



Oxygen and Nitrogen, by diflPerence 21-60 



Sulphur 2-36 



Ash 12-00 



Moisture lost at 100° C 22-10 



100-00 



Another analysis of some of the material that was found 

 as a coating on pieces of the hard grit, which had evidently 

 been completely hardened into rock before its deposition, 

 gave the following results : — 



Per cent. 



Carbon 34-73 



Hydrogen 2-73 



Oxygen and Nitrogen, by difference 22-09 



Sulphur (as above) 2-36 



Ash 18-33 



Moisture lost at 100° C 19-76 



100-00 



The loss on ignition in a closed vessel ' amounts to about 

 75 per cent., but the gases driven off give but little flame, 



