OCEAN CURRENTS 133 



the complicated circulation of the Indian Ocean. It 

 is not without good reason that I call the current 

 system of the Indian Ocean, with its two great off- 

 shoots, the Arabian Sea and the Bay of Bengal, 

 complicated. True, there are complexities in the 

 Atlantic circulation, but they are simplicity itself 

 as compared with those of the Indian Ocean, for 

 here, while there is a vast cold stream bounding 

 its southern verge and thrusting a chilly flood north- 

 ward along the torrid West Australian coast, there is 

 no corresponding force being exerted on the northern 

 boundary, as in the Atlantic and Pacific Oceans. 

 The East Indian archipelago effectually hinders any 

 interference from the great equatorial stream of the 

 Pacific Ocean, and so, bounded by heated land on 

 every side but one, the Indian Ocean has had to 

 develop a circulation peculiarly its own, and not in 

 the least like that of the other oceans. 



Again, in developing this singular circulation the 

 factors have been unusually complex. The evapora- 

 tion, of course, is enormous, and invites the cold water 

 of the Antarctic current to rush in and fill the vacancy ; 

 but there is also the curious atmospheric phenomenon 

 of the north-east monsoon blowing for about six 

 months of the year, and followed by the south-west 

 monsoon. Here let me interpolate what I feel to 

 be a necessary warning, having found so many other- 

 wise well-informed people astray upon the point. The 

 title "monsoon" is derived from the Persian word 

 mousum, signifying season. (The orthography being 

 phonetic is doubtful.) It does not mean a necessarily 

 stormy wind, but a seasonal wind, and to confound 

 it with a hurricane, a cyclone, or a typhoon is quite 



