512 
VAST AMOUNT OF SUBSIDENCE 
CHAP. XX 
there subsided, and in each atoll a monument over an island 
now lost. We may thus, like unto a geologist who had lived 
his ten thousand years and kept a record of the passing 
changes, gain some insight into the great system by which 
the surface of this globe has been broken up, and land and 
water interchanged. 
BIRGOS LATRO, KEELING ISLAND. 
