10 
THE GEOLOGIST, 
Tn the cliffs to the south of Portnoffer, adjoining the Causeway, 
which average from two hundred and seventy feet to three hundred 
and seven feet in elevation (fig. (3), the two cohimnar beds, which 
2S0/eet 
Ugn. O.-Cliffa South of Portaofler. 
Ligii. 7.— The Whin Dyke. 
are so distinct at the summit of the " Chimney-" headland, are repre- 
sented by not less than possibly four separate deposits of trap ; the 
