222 ACCOUNT OF THE AUCTIC REGIONS. 



traction is diminished, and the waves are not so 

 high. Most seamen will have observed, that in 

 strong winds acconjpanied with heavy rain, the sea 

 is seldom very high, and that much less forcible 

 winds, with a dry air, produce higher waves. In 

 this case, it is said, " the rain keeps the sea down." 

 Whatever, therefore, diminishes the friction of 

 the wind in passing over the water, or prevents the 

 attraction of air and water, must operate against the 

 formation of waves. Thus oil scattered on the sea, 

 soon spreads over a great extent of surface, inter- 

 cepts the attraction between the wind and water, 

 and by its smoothness diminishes the friction be- 

 tween the two elements, so as to prevent the for- 

 mation of the rudiments of waves. By subduing 

 the inferior waves, it prevents the higher waves 

 from overrunning them and producing breakers, and 

 thus keeps the surface of the water, however undu- 

 lated, in a smooth and pretty regular surface. A 

 pellicle of ice formed on the sea, interrupts the free 

 mobility of the superficial particles of the water, 

 possibly reduces the friction, and produces a simi- 

 lar effect. 



In temperate and frigid regions, where the winds 

 are very variable and partial, two or three distinct 

 swells, pursuing different courses, are sometimes ob- 

 served at the same time ; and it is a very usual 

 circumstance, in traversing the ocean, to meet with 

 various swells, the evident result of powerful winds. 



