430 PHYSICAL GEOGRAPHY OF THE SEA, AND ITS METEOROLOGY. 



the roots came. Nevertheless, the passage of the meteor, whose 

 narrow path was marlced by devastation, would create a great 

 commotion in the aii-, and there would be high winds raging for 

 several miles on eiiher side of the " wind-road." But (§ 799) let 

 US consider for a moment the effect of the diurnal rotation of the 

 earth upon one of these revolving discs 1000 miles in diameter : 

 its height would scarcely be two miles, and its thickness would 

 not be as great, in proportion to its diameter, as half the thickness 

 of this leaf is to the length of an inch. Now the difference in 

 rate of the diurnal rotation between the northern and southern 

 limbs of the disc would be sufficient, irrespective of any other 

 power, to break it up. Suppose its southern limb to be in 20° 

 N., its northern limb would be 1000 miles, say 17°, farther 

 north, that is, in 37°. Diurnal rotation would carry to the east 

 the air in the southern limb at the rate of 845 miles an hour ; 

 but when this same air comes round on the northern limb, 

 diurnal rotation would carry it eastward at the rate only of 720 

 miles. Because the wind hauls in a particular way, it does 

 not follow, as by diagram (§ 799) it has been shown, that it 

 is blowing in a circle, or that the centre of the storm is at right 

 angles to its line of direction. 



807. Extra-tropical gales. — In the extra-tropical regions of each 

 hemisphere furious gales of wind also occur. One of these, 

 remarkable for its violent effects, was encountered on the 24th of 

 December, 1853, about three hundred miles from Sandy Plook, 

 latitude 39° north, longitude 70° west, by the " San Francisco," 

 steam-ship. That ship was made a complete wieck in a few 

 moments, and she was abandoned by the survivors, after in- 

 credible hardships, exertions, and sufferings. Some months 

 after this disaster I received by the California mail the abstract 

 log of the fme clipper ship " Eagle Wing" (Ebenezer H. Linnell), 

 from Boston to San Francisco. She encountered the ill-fated 

 steamer's gale, and thus describes it: ^^ December 24:tJi. Latitude 

 39° 15' north, longitude 62° 32' west. First part threatening 

 weather ; shortened sail ; at 4 r.iM. close-reefed the top-sails and 

 furled the courses. At 8 p.m. took in fore and mizen top-sails ; 

 hove to imder close-reefed main top-sail and spencer, the ship 

 lying with her lee rail under water, nearly on her beam-ends. 

 At 1 30 A.M. the fore and main top-gallant-masts went over the 

 side, it blowing a perfect hurricane. At 8 a.m., moderated ; 

 a sea took away jib-boom and bowsprit cap. In my thirty-one 



