PHYSIOGRAPHY OF EASTERN NEW GUINEA, ETC. 101 
whole district is built up of vast beds of yellow ash and 
pumice, sprinkled with scoria. The Jatest crater is a cinder- 
cone. Although the activity of this system seems to be 
expiring, yet the corditions described in the preceding 
subsections indicate the presence of forces sufficient not 
merely to cause a continuance of quiet activity but a sudden 
renewal of an intense explosive character. 
(a1) PrysiograpHy.—The following subjects will be 
dealt with under this subsection :— 
(1) General physiography— 
(a) The trend-lines of New Guinea; 
(b) New Britain an area of subsidence ; 
(c) New Ireland an area of uplift: 
(2) Relation to the general topography of South- 
western Pacific: 
(3) Relation to the earth movements: 
(4) Relation to Australia. 
(1) New Guinea, New. Britain, and New Ireland.—In 
discussing the physiography of this area, it must be kept 
in mind that we are considering the marginal portion of the 
anclent continental area which originally ineluded Aus- 
tralia, New Guinea, and surrounding islands—Solomons, 
New Hebrides, Fiji, New Caledonia, Tonga, Kermadec, New 
Zealand, and very possibly the East Indies.t From its 
relation to the Pacific Ocean and the continental mass, the 
area has been subjected to great stress movements. 
The dominant trend-lines of this portion of the South- 
western Pacific are generally north-west to south-east. A 
difficulty is, however, presented by the general west-to-east 
trend of the great peninsula of New Guinea and the island 
of New Britain. Professor David, in the ‘‘ Federal Hand- 
book,’’ describes New Britain as a probable virgation of 
the west-to-east trend of Western New Guinea. Protessor 
Suess, in ‘‘Face of the Earth,’’ vol. iv, considers the 
direction of the voleanic range in New Britain to be a 
difficulty in his theory of the Australian arcs. The writer 
ventures to suggest a theory, based on many personal 
observations, that will account for the present topography 
of the area. 
4 See paper by H. C. Abendanon: Jour. of Geol., vol. 27, 1919. 
