8 
TIITl GEOLOGIST. 
The section ai the Chimney-headland is as follows : commencing 
at the top, two thicl< beds of columnar basalt, closely resembling 
each other in ap^ioarance, a few columns of the top one being left 
standing apart fi oni the main mass at the edge of the cliff, thus sug- 
gesting the idea of the " chimney ;" the tloor of the upper bed is re- 
markably level. These columnar basalts rest on what is known as 
the great ochre bed — a well marked feature in the section. Below 
this ochre layer the remainder of the cliff consists of possibly four 
deposits of amorphous basalt, each separated from the other by a 
thin layer of ochre. 
In the lesser headland, east of Portnoffer Bay, the section is very 
similar to that just described ; the two upper columnar beds are 
again recognized, and together rest on the ochre bed, which here, 
however, has become considerably thinner, and, owing to a steady 
dip of about five degrees to the west in all the beds at that side of the 
Chinmey-head, it is now much nearer to the sea than before ; this 
may be the result of a shght upheaval en masse of the beds at the 
Cliimney -headland. 
Lign. 5.— The " Organ." 
If we attempt to follow the great ochre bed towards the Cause- 
way, or in its western extension, it appears to thin out, and to 
be easily concealed by the debris from the cliffs above, and 
eventually a very marked change is observed in the superimposed 
