87 



six feet high facing the sea, a large flat piece of the pitch about 

 15 inches long was taken from the face of the sand bank about 

 one foot from the bottom. 



2. The specimens above mentioned were found on the beach, 

 near high-water mark. A few small fragments were picked up 

 amongst the sandhills, to about a mile from the coast. They 

 showed fresh conchoidal fractures. 



3. In no case was the material found either included within a 

 rock or filling the crevices of a rock. 



4. In conversation with Mr. Buck, of Point Marsden, who had 

 for many years in earlier life been in the sealing trade, I was told 

 that the old sealers not only were acquainted with its occurrence 

 on the coast, but used it for pitching their boats ; that they found 

 it from Flour Cask Bay, on the eastern side of the Island, as 

 well as at other places along the coast towards the west, around 

 the south end of Eyre's Peninsula, and on the adjacent islands, 

 and as far west as Cape Aird in Western Australia. In all 

 instances it was picked up at or about high-water mark. 



[A substance precisely similar has been found on the beach 

 near the extreme south-eastern limits of the State. J 



5. With respect to the black-colored limestones, the conclusion 

 that they owe their color to the presence of bituminous matter is 

 evidently a false inference. Under analysis these black stones 

 yield only a very slight indication of carbon, but a somewhat 

 strong reaction for iron. Whatever may be the cause of this 

 dark coloring, it is certainly not local, except it be from proximity 

 to the sea. I noticed the occurrence of these black limestones, 

 along every part of the coast that I visited, not only along the 

 south coast, but also at QueensclifFe and Cape Willoughby. 

 Where the solid limestone cruse was colored black, it always 

 occurred on the elevated and exposed points, never underground, 

 the reverse of what might have been expected had it arisen from 

 bituminous saturation. I did not notice this effect on limestone 

 distant from the sea. My first impression was that these black 

 stones were stained by successive growths of a black lichen which 

 has its habitat on limestones that are situated within reach of 

 the sea spray or strong sea air, and that the vegetable growth 

 kept pace with the travertine growth, successive growths being 

 incorporated in the stone producing a black carbonaceous stain. 

 The analyses referred to point to a mineral rather than a vege- 

 table origin of this curious effect. 



In relation to the occurrence of the asphaltum material the 

 following deductions appear to be justified : — 



1. It is self-evident that the material has not been formed 

 where found, and must therefore have travelled, more or less,, 

 from its original source. This is shown by (a) its fragmentary 



