182 LIGHT SCIENCE FOR LEISURE HOURS. 



great Gulf Stream, which sweeps from equatorial 

 regions into the Gulf of Mexico, and thence across the 

 Atlantic to the shores of Western Europe. In the 

 South Indian Ocean there is the "south equatorial 

 current" which sweeps past Mauritius and Bourbon, 

 and thence returns toward the east. In the Chinese 

 Sea, there is the north equatorial current, which 

 sweeps round the East-Indian Archipelago, and then 

 merges into the Japanese current. There is also the 

 current in the Bay of Bengal, flowing through the 

 region in which, as we have seen, cyclones are com- 

 monly met with. There are other sea-currents besides 

 these which yet breed no cyclones. But we may 

 notice two peculiarities in the currents we have named. 

 They all flow from equatorial to temperate regions, 

 and, secondly, they are all u horseshoe currents." So 

 far as we are aware, there is but one other current 

 which presents both these pecularities, namely the 

 great Australian current between New Zealand and 

 the eastern shores of Australia. "We have not yet 

 met with any record of cyclones occurring over the 

 Australian current, but heavy storms are known to 

 prevail in that region, and we believe that when these 

 storms have been studied as closely as the storms in 

 better-known regions, they will be found to present the 

 true cyclonic character. 



Now. if we inquire why an ocean-current travelling 

 from the equator should be a "storm-breeder," we shall 



