IS FINGAL'S CAVE ARTIFICIAL? 



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in a " gravelly " beach, where a boat may be drawn up. It is 50 feet 

 high, 48 feet broad, and 224 feet long. It is excavated in the lower 

 stratum. Thus two tunnels of the same dimensions are supposed to 

 have been driven into two different materials by the same force. The 

 interior dimensions are nearly the same to the end. As no sentimental 

 or religious motive can be assigned to Nature for this freak, it is amen- 

 able to comparison. The Blue Grotto of Capri is typical. Its entrance 

 is scarcely three feet in height ; in the interior the roof rises to a 

 height of 41 feet ; the water is 8 fathoms deep ; length of the grotto, 



Fig. 5. Fingal'8 Cave (looking out), showing Iona, distant Sis Miles. 



175 feet ; greatest width, 100 feet. Here the great size of the aper- 

 ture is further increased. The superior part of the front, penetrating 

 into the columnar basalt, has hollowed a recess above the main open- 

 ing. The same Gothic tympanum, distorted by the material, not only 

 marks its artificial origin, but disproves the allegation that the col- 

 umns could not form a natural architrave. The Boat Cave is acces- 

 sible only by sea. It is a long opening, resembling the gallery of a 



