364 Transactions.— Geology. 
In New Zealand we see a line of extinct volcanoes, at the Waiau, 
Dunedin, Timaru, Lyttelton, and the Kaikoras, flanking the main range of 
the Southern Alps. 
In 1835, at the moment when the coast of Chili was shaken by a violent 
earthquake, a submarine volcano burst out near Juan Fernandez, fully 
three hundred miles away from the centre of elevation. 
That voleanic eruptions are most violent when different lines of eleva- 
tion intersect each other, is proved wherever such intersections occur. 
In New Zealand we have one such line passing along the South Island 
and thence to East Cape in the North Island, reappearing again probably 
at Samoa and the Sandwich Islands. This line is intersected between 
Tongariro and White Island by another line which forms the north part of 
the North Island; a line of active voleanoes and hot springs marking the 
intersection. 
That Auckland does not belong to the same volcanic area as the rest 
of New Zealand is, I think, proved by the fact that only two out of the 
234 shocks of earthquake which have been recorded have been felt there. 
One of them was felt nowhere else, the other was felt as a severe shock in 
every other town and in Auckland only as a very slight one. This fact is 
very remarkable, as Auckland is situated in the centre of a perfect nest of 
voleanic cones, and is, of all the places in the Colony, the one where 
manifestations of present activity would be looked for. 
The most active volcanic area in the world is the group of islands 
around Borneo. Here three great lines of elevation intersect each other, 
one forming the Malay Peninsula, another passing through the Phillipines 
to Japan, and the third forming Sumatra, Java, and New Guinea, and 
after passing through New Caledonia terminating in the Province of 
Auckland, unless it again reappears in the Chatham Islands. 
Another area scarcely less active than the above is formed by the inter- 
section with the Andes of the line which forms the islands of Jamaica, 
San Dominga, and Puerto Rico. 
* On the theory that the lava poured out by a volcano is derived from 
the fluid centre of the earth, it has puzzled speculators to account for 
many peculiar occurrences which are capable of easy solution by the » hype 
thesis which I have brought before you. 
In March, 1861, the town of Mendoza was destroyed and 10,000 of its 
inhabitants killed by an earthquake, which was not felt on the other side 
of the range, only a few miles distant. If earthquakes are due to the 
sudden explosion of gas from the greatest depths of the earth, how can 
their.effects be so local? If, however, they are due to the sudden fracture 
of a comparatively thin sheet of rock, there is no difficulty in understanding 
