322 
PACIFIC SCIENCE, Vol. XIX, July 1965 
Fig. 1. Map of the island of Hawaii, showing the locations of the major volcanoes, the calderas ( solid black 
spots), and the approximate centers of the gravity highs ( black triangles ) as located by Kinoshita et al. (1963). 
of the sharply defined central depression only, 
whereas those of 1924 and 1955 include the 
volume of a gentle sinking of the mountaintop 
that could not have been detected without sensi- 
tive tiltmeters or precise surveying, so that 
actually the early collapses must have been 
somewhat larger in relation to the later ones 
than is indicated by the table. 
The history of Mokuaweoweo is known in 
far less detail. A large collapse of the caldera 
floor in the middle part of the 19th century 
may have been associated with one, or possibly 
more than one, of the flank eruptions of Mauna 
Loa. Since then the depression has been grad- 
ually refilled, until in 1949 lava poured out of 
the caldera into South Pit, filled it to over- 
