BY H. I. JENSEN. 659 



and extinction is approaching. Should the lava-tunnel plug up, 

 and the same crater continue active, several fine villages would 

 be in danger of destruction. 



It is interesting to note that both the new craters (1902 and 

 1905-6) are situated on the northern slopes of the backbone of 

 Savaii, and broke out in fresh places but only a few miles from 

 old and well-marked craters. Possibly the line of weakness has 

 moved northwards. 



Mr. von cler Heide described to me a small pillar seen by him 

 in the crater. On my visit I did not see it, but from the descrip- 

 tion, I take it to be a driplet cone. 



The foregoing description of the flows, as well as the peno- 

 logical investigation of the rocks, bring out a close correspondence 

 between the volcanoes of Savaii and those of Hawaii. The lavas 

 are of the same type, and their modes of eruption, flow, and 

 cooling are similar in the two localities. In the production of 

 long flows sloping gently towards the sea, and, in the quiet way 

 lava is poured steadily to the sea, the new Savaiian volcano 

 resembles Mount Loa in Hawaii. 



Simultaneous eruptions in other places. — It is interesting to 

 note that early this year (1906) when the Savaiian volcano 

 displayed its maximum energy, a sympathetic outbreak occurred 

 in the island of Tofua in the Tongan group. The Rev. Walkden 

 Browne, of Tongatabu, who visited the island during the out- 

 break, gave me a short account of the event. In January the 

 Tofuan volcanoes burst out into eruption and remained active for 

 about two months. There are two cones on the island, which 

 were both active. Many other small craters exist in various 

 parts. The island is about six miles by five, and constitues in 

 fact a single volcano whose summit has been blown off. The rim 

 of the island is 1800 feet high all round, and one ascends rapidly 

 from the sea. The descent to the interior of the island is again 

 steep. In the centre of the island there is a lake whose level is 

 probably 400 feet above the sea. The two cones that were active 

 stand east of the lake. The higher and more easterly only 

 smoked during the eruption, but the smaller cone was in violent 



