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PACIFIC SCIENCE, Voi XX, January 1966 
Fig. 7. Map of normally submerged marine shelf projecting from south shore of Kapu-wai cove, Honau- 
nau Bay. (Map made by Gilbert M. Tanaka, National Park Service, U. S. Dept, of the Interior, at 8 AM, 
June 8, 1964.) 
shows the usual present-day appearance of the 
.shelf area, with a wave breaking over its western 
edge. Figure 9 shows how the exposed shelf ap- 
peared at 8 AM on June 8, 1964. 
It is significant that the shelf is unnamed. In 
1919, Stokes collected place names for almost all 
of the minor coastal features in the area, and 
apparently the large shelf was not mentioned. It 
had been ''lost” for so long that apparently its 
name and former uses had been forgotten by 
1919. 
It does not seem logical to assume that the an- 
cient Hawaiians labored with hammer stones 
and pounders to abrade the artificial concavities, 
especially the papamu, for use only at low tide. 
Bait cups and tanning tubs would be useless if 
they were submerged. There seems to be little 
question that this tremendous labor went to 
make features on land which was normally dry, 
and that since the time when these features were 
made the land has sunk or the water level has 
risen. 
Without a firm reference point in position 
and time, it is difficult to estimate the amount 
of rise of mean sea level relative to the land dur- 
ing contemporary times. Unfortunately, no sur- 
veyor set precise benchmarks in 1764. However, 
we estimate that the relative rise of mean sea 
level during the last 200 years has been ap- 
proximately 2 ft. This change helps to explain 
why the numerous artificial concavities are now 
usually under water, as well as explaining the 
