18 - MR GOODCHILD ON 
Sir John gave an address on “Coral Reefs and Islands” to 
the Royal Society of Edinburgh :—“ The problem for which 
the various hypotheses had been put forward was to account 
for the narrow rim of coral reefs and coral islets enclosing 
a shallow water lagoon, while the water to the outside, not 
far from the edge of the reef, was frequently one or two 
miles in depth. Chamisso, in 1820, said the form of reefs 
was due to the natural growth of the corals and the action 
of the waves. Other naturalists held that these reefs were 
built up on the rims of volcanic craters. During the voyage 
of the Beagle, Darwin published his celebrated theory, which 
accounted for the appearances by the slow sinking of the 
coasts, and the equally slow building upwards of the coral 
organisms. This theory was universally accepted for nearly 
half a century, although Le Conte pointed out that it did 
not apply in the case of the West Indian reefs. Rein said 
the same with respect to the Bermudas, and Semper said it 
was in no way applicable to the Pelew Islands. Darwin 
stated that his whole theory was thought out on the west 
coast of South America before he had seen a true coral reef, 
and that he had therefore only to verify and extend his 
views by a careful examination of living reefs. Dr Murray 
held that the views which he published after the return of 
the Challenger expedition were arrived at by the true in- 
ductive method. To a large extent they were a return to 
the views of Chamisso. The lecturer pointed out how banks 
were formed in the great oceans by the degradation of 
voleanic and other islands down to the lower limit of wave 
action, and further, that volcanic cones, which did not reach 
to the level of the sea, were continually being built up to 
the lower limit of wave action by an accumulation on their 
summits of marine deposits. They had an example of the 
first method now in progress in the case of Falcon Island, 
near the Friendly Islands, which, after being thrown up 
several hundred feet above the sea, was now almost com- 
pletely washed away, and on the spot a bank had been 
formed at the lower limit of wave action. Thus was formed 
a bank on which future coral reefs might be built up. In 
the same ocean the Admiralty surveyors had found a large 
number of banks at from 30 to 40 feet below the level of 
