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The boreholes on Funafuti, at the site now called Darwin's Drill, are the result of drilling conducted by the Royal Society of London for the purpose of investigating the formation of coral reefs to determine whether traces of shallow water organisms could be found at depth in the coral of Pacific atolls. This investigation followed the work on The Structure and Distribution of Coral Reefs conducted by Charles Darwin in the Pacific. Drilling occurred in 1896, 1897 and 1898. Professor Edgeworth David of the University of Sydney was a member of the 1896 "Funafuti Coral Reef Boring Expedition of the Royal Society", under Professor William Sollas and lead the expedition in 1897. Photographers on these trips recorded people, communities, and scenes at Funafuti.

What formations was the Royal Society studying?
coral reefs