182 



8CIE]S'CE. 



[ToL. IX., No. 213 



porary lakes of fire appear on all sides, but Hale- 

 ma'uma'u remains essentially constant. This is a 

 real crater, while Captain Button has well sug- 

 gested the name of ' caldera ' for the entire de- 

 pression. 



The entire pit was never fuller than on the 

 evening of March 6, 1886. The lava that for nine 

 years, or since the last previous important dis- 

 charge (1877), had been accumulating and pouring 

 over the floor from Halema'uma'u and New Lake, 

 till it attained the altitude of 3,719 feet above the 



some of them probably occasioned by the falling 

 of large masses of rock. Shortly after midnight 

 the lava disappeared through a subterranean chan- 

 nel, filling up some vacant chamber, probably, 

 since it did not discharge anywhere at the surface, 

 nor was there any oceanic disturbance within easy 

 distance of the island. The thickness of the 

 molten column that disappeared proves to be 570 

 feet, without estimating the additional distance 

 to the unknown reservoir beneath the rough fal- 

 len fragments. 



Pig. 1. — Cavity once occupied by the New Lake. 



sea-level. The floor was convex, and 160 feet 

 higher at the lakes than at the northern edge, 

 while the general level averaged from 150 to 200 

 feet above the black ledge of Wilkes. To the 

 south the lava had risen upon the old sulphur- 

 banks, nearly covering them, while leaving a long 

 narrow promontory scarcely a dozen feet above 

 the general level. Late in the evening there com- 

 menced a series of earthquakes, so severe as to 

 alarm J. H. Maby, the landlord of the Volcano 

 House, and his household. Up to 8 a.m. of the 

 following day, forty-three shocks were noted. 



The map gives a correct delineation of the 

 sunken area. The main depression is roughly tri- 

 angular, with sides about 3,350 feet long, forming 

 an area less than half a mile square. In extent 

 it is not very unlike Kilauea Iki, thouglT the 

 basin carries less cubical content. To the east of 

 the principal depression is the space left by New 

 Lake and Little Beggar, the smaller temporary 

 craters. The average depth of this circular seg- 

 ment is 165 feet ; the length, 1,700 feet ; width, 

 250 to 650 feet. It is a sort of shelf or terrace ad- 

 joining the greater depression. The triangular pit 



