198 CORALS AND CORAL ISLANDS. 
of beach, for a height of two to three feet, the coral reef-rock 
was exposed, indicating an elevation of the island. For three 
or four feet above this, layers of the beach sand-rock were 
often in view, consisting of coral pebbles firmly cemented, and 
having the usual dip of seven or eight degrees seaward ; in 
many places it was concealed by the beach sands and pebbles. 
There was no growing coral on the platform, excepting Nulli- 
pores. The outer margin of this platform was very uneven, 
and much intersected by channels, though less so than at 
Enderbury’s Island. Great numbers of Birgi (large Crustacea) 
were burrowing over the island, some of which were six 
inches in breadth. 
Oatafu or Duke of York’s. — 8° 38'S. 172°27'W. Form 
oblong, trending northwest. Length 33 miles; breadth 2 miles. 
Circuit 94 miles, and about one-half wooded in patches. South- 
west reef mostly bare. A lagoon, but without entrance except 
for canoes at high tide, on leeward side. Island ten feet high. 
Shore platform narrow, and intersected by channels. Shores 
lined by reef-rock, two or three feet out of water, indicating 
an elevation of the island. This reef-rock consists of various 
corals firmly cemented. Within the lagoon, knolls of coral, 
but none near the shore on the leeward side. 
Fakaafo or Bowditch’s. — 9° 20'S. 171° 5’ W. 63 miles 
by 4. Shape nearly triangular. Circuit seventeen miles, 
about six of which are wooded in several patches, separated 
by long bare intervals. A large lagoon, but no ship entrance. 
Height of island, fifteen feet. Width to the lagoon, one hun- 
dred to two hundred yards. Soil of the island coral sand, 
speckled black with results of vegetable decomposition. Shore 
platform narrow. At outer edge a depth of three fathoms, 
and from thence gradually deepens, and abounds in corals 
for fifty yards, when it deepens abruptly. Coral reef-rock 
