NARRATIVE OF THE CRUISE 



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which decorated these caves have all been removed by previous 

 expeditions, although we saw a few fragments here and there. 

 Someone has estimated that thousands of human beings might 

 be accommodated in these tunnels, but it is not clear what purpose 

 they served. Some advance the notion that they were used in 

 times of tribal war; some say that the young girls were secreted 

 here until they were marriageable; but a more reasonable ex- 



"BiHU Rocks" Lying below the Caves on Rano Kao Crater 



Legend says that the man who swam to these rocks and brought back the first eggs of 

 the sooty tern was made king for the ensuing year. 



planation seems to be that they were temporary living-quarters 

 for the population during certain religious festivals and while 

 waiting for the return of the sooty tern to the "Bird Rocks," 

 which lie off the base of the cliffs some thousand feet below. 



To prevent the extermination of the sea-birds and spawning 

 fish, one of the more recent kings made it a capital offense to eat 

 birds' eggs or fish for the two months preceding the return of the 

 sooty tern from the north (usually in September) . He reinforced 

 this taboo by appealing to the vanity of the natives in the follow- 



