1 64 LIGHT SCIENCE FOR LEISURE HOURS. 



But the most remarkable point of Captain Hall's 

 account remains to be mentioned. He had gone out 

 of his course to avoid the storm, but when the wind 

 fell to a moderate gale he thought it a pity to lie so far 

 from his proper course, and made sail to the north- 

 west. 6 In less than two hours the barometer again 

 began to fall and the storm to rage in heavy gusts.' 

 He bore again to the south-east, and the weather 

 rapidly improved. There can be little doubt that but 

 for Captain Hall's knowledge of the law of cyclones, 

 his ship and crew would have been placed in serious 

 jeopardy, since in the heart of a Chinese typhoon a 

 ship has been known to be thrown on her beam-ends 

 when not showing a yard of canvas. 



If we consider the regions in which cyclones appear, 

 the paths they follow, and the direction in which they 

 whirl, we shall be able to form an opinion as to their 

 origin. In the open Pacific Ocean (as its name, indeed, 

 implies) storms are uncommon'; they are infrequent 

 also in the South Atlantic and South Indian Oceans. 

 Around Cape Horn and the Cape of Good Hope, 

 heavy storms prevail, but they are not cyclonic, nor are 

 they equal in fury and frequency, Maury tells us, to 

 the true tornado. Along the equator, and for several 

 degrees on either side of it, cyclones are also unknown. 

 If we turn to a map in which ocean-currents are laid 

 down, we shall see that in every ( cyclone region ' there 

 is a strongly-marked current, and that each current 

 follows closely the track which we have denominated 

 the storm- c. In the North Atlantic we have the 



