SOLOMON ISLANDS. 
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descends more rapidly ; on the weather side at an angle of 
rather more than 20°, on the lee side usually at a smaller 
angle. The highest points (of coral limestone) on the 
southernmost island rise to about 70 feet above the sea. 
It has two lagoons; the deeper is about 9 fathoms, and 
over the bar at its mouth the water is less than a fathom 
deep at low water neaps. 
Mr. Guppy is of opinion that this island commenced its 
history as two flat-topped submerged reefs, and that the 
atoll form has been assumed since these have been up- 
heaved. Santa Anna is an upheaved atoll with shore-reefs 
ranging from 150 to 600 yards wide according to the steep- 
ness of the land. On the westward the shore-reefs enclose a 
circular lagoon 700 to 800 yards wide and 16 to 17 fathoms 
deep. Ugi island lias shore-reefs of varying width, and on 
the east coast the shore-reef encloses a narrow lagoon a 
mile long and 10 fathoms or less in depth. There is also 
in that on the south coast a circular lagoon about 100 yards 
wide and 6 fathoms deep, approached by a narrow channel. 
Bin is a patch of coral reef which has been raised about 
100 feet above the sea, and is still encircled by living 
reefs. Bua Sura is an atoll of elongated form about 3 miles 
in length. Except for three wooded islets on the south 
side, its circumference is either just awash at low tide or 
is within a fathom of the surface ; but soundings in the 
lagoon to a depth of 37 fathoms failed to reach the bottom. 
The islets are at highest only 15 or 20 feet above the sea, 
* cliffs of coral rock 4 or 5 feet in height ’ in one ‘ betokens 
recent elevation of a small amount.’ Eddystone Island 
consists of ‘ two distinct islands (volcanic) which have 
become united by elevation of an intervening coral reef. 
On the east coast the submarine slope down to the 100 
fathom line is from 30° to 35°. There is a hole in the 
middle of the reef on the west side, about 150 yards across 
and 18 fathoms deep which Mr. Guppy thinks may mark 
