412 THE GEOLOGY OF THE NEW HEBRIDES, 



appears to be evidence of the existence of an old crater between 

 Tongoa and Epi. 



ToNGOA, the largest of the three islands, is subcircular in out- 

 line, with an area of about 10 sq.miles. Abutting on to the sea- 

 cliffs at the north side is a district about twenty acres in extent 

 where the ground is heated to almost 212° F.; just three miles 

 N.W. of this point a submarine eruption took place in 1897. A 

 specimen of rock taken from the vicinity of the hot ground has 

 been described by Mr. J. J. H. Teall as an augite andesite. Another 

 specimen of rock from the summit of the highest point on the 

 island — 1674 ft. — examined by the same authority, proved to be 

 basalt. 



Epi is of special interest, as it was briefly visited by the 

 ' Challenger ' Expedition; little examination of the island was, 

 however, then effected, as the scientists during the few hours 

 spent on shore did not venture to wander out of sight of the 

 beach. Dr. J. Murray recorded the existence of raised coral 5 ft. 

 above sea-level, and reported having found water-worn fragments 

 of coral limestone in a creek bed hard by. It is the tracing of these 

 pebbles back to their position in situ that Moseley refers to when, 

 he says that on this occasion Dr. Murray came so near making 

 an important discovery. 



Our examination of the island was limited to short visits at 

 The Foreland and at Diamond Bay. 



The dimensions of the island are approximately 22 miles by 9 

 miles, with an area of 100 sq.miles. The hills run in a W. to 

 K.W. direction, and attain a maximum elevation of 2791 ft. 



The island appears to be wholly composed of volcanic material 

 overlaid by raised coral limestone. Along the west coast cinder 

 beds and soft volcanic tuffs are extensively developed, as also are 

 the overlying limestones. The best section obtained was at The 

 Foreland, (text-fig. 1) where a well developed coral limestone, 

 elevated to a height of at least 100 ft., caps thick beds of gre3dsh- 

 coloured foundation-beds composed partly of organic remains and 

 largely of volcanic cinder(l). In the upper portions of these beds 



