32 Vo!. XL[ir., Art. C. — S. T^uboi : 



The feature of the inside of the crater is always changing. 

 It is habitual that when the vulcanism displays its full energy, 

 lava fills the crater, and on declining, the layer of lava depresses 

 more and more due to it3 own weight, leaving the poripheral 

 parts in the form of terraces. 



In 1874, according to Milne, southwest of the centre of the 

 crater-floor there was a deep hole, from which steam was issuing. 



During the eruption of 1876-77, lava poured out from this 

 hole, and a miniature spatter cone, Naumann's cone {Nin in Figs. 

 18, 19, it 21), was formed on the crater- floor where the hole had 

 previously been. This new cone seems soon to have been blown 

 away on its northwestern side, fo;- when Naumann, Milne, and 

 Wada visited the island during this eruption in January 1877 they 

 found it in this demolished condition. At that time, molten lava 

 is said to liave been seen in the summit pit of Naumann's cone. 



Nineteen years later, when Yamasaki observed the Miliara 

 crater (January 1806), he found that Naumann's cone lacked its 

 northern half. There was an intermediate flat stage at the foot 

 of the crater-wall, and at about the centre of tills stage (i.e. to 

 the east of Naumann's cone) he found a dL'pression with steep 

 walls, at tlie bottom of which, in a round hole (vent or crater-pit), 

 red molten lava could he seen. Thus the vent or the crater-pit 

 of Naumann's cone had gradually sliifted to the east and had 

 transformed itself into the main pit at the time of Yamasaki's 

 visit. 



In the summer of 11)07, Nakamuea and his colleagues sur- 

 veyed in detail tlie inside of the crater. Fig. 18 is a cjpy of the 

 map they made. Comparing this map with Yamasaki's descrip- 

 tions we see that in the meantime (11| years) topographic changes 

 had airain occurred. As shown in Figs. 18 and 21, Naumann's 



