TEELIMIXARY REPORT. 33 



the so-called soapstone of Fiji. I was informed that other island.s in 

 thi.s group, near Tonumeia, in the centre of the Nonnika plateau, were 

 volcanic. Mango, as we could see it from cm- anchorage, appeared to 

 be volcanic. So that this part of the Tongas is, like the Lau Group 

 in Fiji, made up of islands in part volcanic and in part composed of 

 elevated coralliferous limestone. The eastern edge of the Nomuka 

 plateau (which we did not visit) is edged with small low islands. We 

 merely steamed by the western islands of the Haapai Group, but close 

 enough to see that Tongua, Kotu, and Fotuhaa, which vary in height 

 from 120 to 200 feet, are composed of elevated limestone. The eastern 

 flank of the Haapai plateau is edged with long, low islands, with exten- 

 sive coral reefs along the reef flats of these islnnds. 



The Haapai plateau is triangular, with isolated islands rising on the 

 northwestern side from the deep water separating it from the Vavau 

 plateau. It is separated from the Nomuka plateau by a narrow channel 

 with over 300 fathoms of water. 



The northernmost plateau of the broad ridge of the Tonga Islands is 

 the Vavau plateau. This is elliptical, with a long tongue extending on 

 the eastern face of the ridge toward the northern point of the Haapai 

 plateau, ending in isolated banks (the Disney reef and Falcon bank), 

 lying to the northward of the broad channel, with over 400 fathoms 

 separating it from the Haapai Group. The Vavau Group is by far the 

 most picturesque of the Tonga Islands. It consists of the principal 

 island of Vavau, extending across the northern part of the Vavau 

 plateau. Several parts of the island of Vavau, as at the southwestern 

 extremity, at the entrance to the harbor of Neiafu, and at Neiafu, are 

 finely terraced ; four terraces are indicated there, and other flat-topped 

 smaller islands show traces of two or three terraces. The northern edge 

 of Vavau Island rises to a height of more than 500 feet, and slopes in 

 a general way southward and inland. The southern shore is deeply 

 indented by bays and sounds, and flanked by innumerable islands and 

 islets, some of con.siderable height (150 to 250 feet) which gradually 

 become smaller and smaller as they rise toward the southward and east- 

 ward, these islands having been formed from the denudation and erosion 



