THE GREAT ERUPTION OF SAKURA-JIMA IN 1914. 165 



from the enclosing one of 1779 in its being of low altitude and 

 fi-om the tradition of the people, especially the formation of 

 Omoyé-zaki or the ' burning headland ' of whicli we have an 

 authentic record. 



c) Pétrographie Characters.— The material of lava (PI. XVIII. 

 Figs. 2-3) is white-spotted (1-4 mm.), dopatic, slightly slaggy j^'^tch- 

 black rock which, when seen under the microscope, is exactly like 

 the younger lavas of 1779, later to be described. It is a pyroxene- 

 andcsite with the groundmass of dark brown glass in which rather 

 coarse microlites (0.06 mm.) of dusted augite and skeletal plagio- 

 clase swim in fluidal arrangement. The relative quantity of the 

 two species of microhtes is variable, although that of augite always 

 predominates over the other. Pyroxene phenocrysts are scanty 

 and both members are variably represented. 



ß) The Nabé-yama and Yébino-tsuka Homates. (East Side.) 



a) The Nabé-yama Homate.— Contemporaneously with the activity 

 and the outpouring of lava in 1471, Nabé-yama seems to have 

 been also active. Mr. Ijichi in his oft-cited work : ' On the erup- 

 tion of Sakura-jima in the An-ei era,' incidentally mentioned that 

 the kettle (nabé)- shaped Nabé-yama is a relic of the eruption in 

 1471. He compared its position to the main Sakura-jima just as 

 the parasitic knob of Hoyei-zan is related to Fuji-san. Particulars 

 about its activity are not recorded in any work at the writer's 

 disposal. (Geologic Map, hn.) 



This model-like ringwall hill is located on the southeast slope 

 and rises on a base of l.?)hn. in diameter 328 ??2. high. The 

 outer slope of regular ringwall is tolerably steep, but the deep 

 inside is still more precipitous, and the circular wall is only 



