4i 
laid by white limestone. Alternations of these lavas and coral lime- 
stones were observed up to a height of 2,000 feet ; at this point a bed 
of white coral limestone was encountered, forming a conspicuous cliff 
called by the natives Korada. From Tauputa, I skirted the coast as 
far as Agonai ; there was practically no beach, for the land plunged 
down suddenly into deep water. The coast in this neighbourhood 
being practically timberless, the bold cliffs afforded splendid 
opportunities of studying the geology. I could see from the boat 
several conspicuous limestone escarpments at all attitudes above sea 
level. 
IGNEOUS ROCKS. 
Next to the elevated reef masses, the volcanic phenomena of 
British New Guinea arrest the attention of the observer. With refer- 
ence to this subject, I cannot refrain from quoting a passage from 
Macgillivray’s “Voyage of H.M.S. Rattlesnake,” in which it is 
observed that : — “The fact of the existance of several active volcanoes 
on islands immediately adjacent to the north-east of New Guinea (first 
made known by Dampier), and the circumstance of volcanic bands 
traversing the length of many of the great islands of the Malayan 
Archipelago and others, as far to the southward as New Caledonia and 
New Zealand, rendered it extremely probable that we should have 
found indisputable signs of comparatively recent volcanic action in the 
south-east part of New Guinea. We saw no volcanoes, however, and 
the great central mountain chain appeared to me to be probably 
granite.” On a later page, in the second volume, remark is also made 
of “ the total absence of signs of volcanic agency” in the Louisiade 
Archipelago. Observations, however, showed that both active and ex- 
tinct craters in addition to other manifestations of volcanic activity do 
exist all over the Jolony, though in localities which, however, could 
hardly have been examined by Mr. Macgillivray. 
My first acquaintance with the volcanic phenomena was made 
during a traverse from Port Moresby to the Astrolabe Range. This 
range, which forms a tableland at the foot of the backbone of New 
Guinea, appears to have been first described by Macgillivray. He says : — 
“ Mount Astrolabe differs in character from any other of the New Guinea 
mountains seen by us, indicating a different geological formation. 
The summit extends thirteen miles, running parallel with the coast 
line, and distant from it about eight miles. Viewed from the south- 
westward, the outline is irregular, exhibiting a series ol nearly flat tops 
with slight interruptions, but trom the southward it appears as a suc- 
cession of terraces or projecting cliffs, precipitous in front near the 
summit, with a long, steep slope below, probably the debris, while the 
flat top slopes backward with a very gentle declivity.”! 
t Macgillivray, J. Voyage of H.M.S. “ Rattlesnake,” Voi. II., p. 60. 
London, 1852. 
