THE MALAYAN ARCHIPELAGO. Ill 



however, from the map subjoined to Schneider's paper,''^^ gianite 

 and metamorpliic schists, together with a complex of limestone, 

 appear to build up Gilolo, Batian, the non-volcanic Great Obi 

 (Ombira), and the Sula islands, all included in the Moluccas 

 or Spice Islands. According to the recent observations of Kü- 

 kenthal and Retzgers,*''' Gilolo's geologic elements are crystalline 

 schists, peridotite, andésite, and other neo-volcanics, besides coral- 

 limestones. Batian is in part andesitic, with some traces of hot 

 springs, and a doubtful volcanic cone. 



Alono; the west coast of Gilolo,'^''^ a volcanic chain starts from 

 Makian,''"^ and proceeds, quite independent of the Banda volca- 

 noes, through Tidore, Mitara, Ternate, and Hiri, whence it enters 

 the north arm of Gilolo which carries the Guuuugs Tala, Duon, 

 Todekku, Onu, Gamma-Kunorra, Tubaru, and then passes into 

 the Tolo group near Galela Bay, here embracing Tarakan, Ma- 

 nuya, Tobelo, and Duko, the last of which made an eruption in 

 1550, accompanied by earthquakes.*^^^ The andesitic Tidore is an 

 extinct-volcanic island, with hot springs near the shore. Makiau 

 made eruptions in April, 1760, 1819, 1846, and in December, 



64) Jahrb. d. k. k. geol. Reichsamiall, 1876, p. 113 et seq. 



65) Works of both authors are cited in K. Martin's ' Keisen in den Mohikken ', Geolo- 

 gischer Theil, Iste Lieferung, 1897. 



66) Wiclnnann, ' Die Binnenseen von Celebes ', Petermanns MiitlicUunc/en, 1893, p. 3. 



67) K. Martin in the work cited above, seems to be at variance with Wichmann as to 

 the starting point of the Mohiccan volcanic chain. Martin is disposed to think the chain 

 passes southwards through Batian and Manipa Strait to Wawani in Amboina. As the test 

 point of its substantial continuity, which seems to him to withstand any serious objections 

 that might be raised against it, he produces the fact of tlie synchronous occurrence of subter- 

 ranean convulsions ; for, these events happened almost simultaneously : 



20th, May, 1673. Explosion of the Gamma Kunorra in Gilolo. 



12th, July. 1673. Earthquake in Amboina. 



12th, August, 1673. Explosion of Gamma Lamma in Ternate. 

 17th, February, 1674. Exjilosion of Wawani in Amboina. 



68) Wichmann, 'Der Ausbruch des Vulkans Tolo in llalmahera', Zeiischr. d. Deutsch, 

 geol Gesell. 1897, p. 159. 



