Phillips. ^-0» the Volcanoes of the Pacific. 527 



perhaps I had better say as if internal volcanic energy, like 

 the atmosphere, was and is subject to the diurnal revolution 

 of the planet. I think I am justified in saying that it would 

 be so in the original coolmg of our earth's crust, and this 

 quite apart from the great work performed by sedimentary 

 deposit in forming the crust. 



In a paper contributed to volume ix. of our Transactions 

 I tabulated the formation of the various groups of islands in 

 the Pacific as follows : Volcanic — Bonin Islands, Ladrones, 

 Carolines, Sandwich, Marquesas, Society and Georgian, Cook, 

 Samoan, Tonga, Fiji, New Hebrides, Banks, Santa Cruz, 

 Solomons, New Ireland, and New Britain ; coral — Marshall, 

 Gilberts, Paumotus, Phoenix, Union, Loyalty, New Cale- 

 donia. But this tabulation was only a rough one, as I 

 pointed out at the time that the Carolines, Cook, and Tonga 

 Islands were of both volcanic and coral formation. Thus 

 the hill at Neafu (Vavau, Tonga), called " Tolau " (from 

 which visitors gaze upon one of the finest harbours in tiie 

 Pacific, and as beautiful a scene as any one could wish to 

 see), struck me as being formed by a volcanic blow of 

 lava, which, disintegrating in the course of time, gives the 

 present excellent chocolaue - coloured soil around it. The 

 coral, too, in the boat-cave at the entrance to the harbour, 

 which visitors should see, is split in all directions by volcanic 

 upheaval. • (This cave is situated within a mile of Mariner's 

 Cave, described by Byron.) The Island of Vavau is there- 

 fore both of coral and volcanic formation ; indeed, all coral 

 islands may be said to have a volcanic base. 



A great number of the low coral islands in the Pacific 

 have a lake in the centre, showing volcanic subsidence, or, 

 rather, upheaval and subsidence, more than anything else. 

 Nor is it very curious, seeing their origin, that these lakes 

 should be composed of mineral water. The lake at White 

 Island (New Zealand) is, I believe, hydrochloric acid. The 

 whole Pacific bed is blistered with volcanoes. 



I looked at the lake immediately at the back of Nukualofa 

 (Tonga), and speculated as to the time when it was so 

 formed — far anterior to the date of the Langiis. On the 

 other hand, I have run aground upon an atoll, and wondered 

 whether it was from the top of a crater that the coral polyp 

 had begun its labour or a hill-top only of the supposed great 

 sunken continent. There does not appear to be anything 

 like the volcanic action in the equatorial belts of the Atlantic 

 or Indian Oceans that we find in the Pacific, or we should 

 have far more numerous islands in those oceans ; so that, 

 when considering geological questions in the Pacific, we are 

 bound to take into account the terrific volcanic agencv always 

 at work. True, there are extinct volcanoes and lava-beds in 



