NATURAL COLONISATION METHODS 293 



Australia, and from the islands of the eastern end of the 

 Malayan chain ; and most of the plants which have become 

 established in the atoll are represented in Timor, and in Java. 

 It is certain also that the pumice came from Java, and from 

 Sumbawa ; for the advent of the Krakatua pumice is well 

 remembered after the eruption. The floating coral has, like 

 all its kind, a wide distribution, and does not help in the 

 determination of the direction of the sea- trend. 



One piece of flotsam cast on the beaches of the southern 

 islands tells far more definitely of its origin. A boat came 

 ashore some years ago, which in its lines differed from any 

 that the men of Malay countries build. It was in very 

 perfect condition when it was first found, and the carving on 

 it was so well preserved that the Governor had no doubt at all 

 that it was a war canoe from New Zealand, a craft with which 

 he was familiar. 



It is, therefore, safe to conclude that the currents which 

 bring the floating things to the atoll come from the east, and 

 such ocean drifts are, of course, charted. Through Torres 

 Straits the waters of the Pacific Ocean sweep into the Indian 

 Ocean, right to its western limits at the shores of Africa. 

 The waters that wash the northern shores of Australia and 

 the southern shores of the Malayan Islands are, therefore, the 

 carriers of the sea-drift which is likely to be cast up in Cocos- 

 Keeling atoll. 



The track of the drift which leaves the islands is more 

 easily followed, and, in order to learn something of it, I set 

 adrift a number of bottles from the lee side of the atoll. In 

 order to make the experiment yield a true index of drift 

 action only, I loaded the bottles so that they floated with none 

 of their surface exposed, on which the winds could act ; and 

 as they bobbed about in the waves, only a very small portion 

 of the neck came out of water. Within each bottle I put a 

 note, asking the finder if he would help me by writing to me 

 and telling me of his find. I enclosed a small coin to reward 

 him, and to cover his postage ; I sealed the message in a test- 

 tube, put it in the bottle, and launched the whole afiair, 



