DISCUSSION AND ANALYSIS OF WINDS. 679 



largely if we take into account the number of miles. And this may be clone 

 safely, as the expedition of Capt. Hall had an anemograph of Robinson's plan. 

 The east winds then seem to be a weak local land-wind, caused by the difference 

 of temperature of land and sea. The N. E. winds, on the contrary, are the true 

 polar currents, flowing towards the barometric depression about Iceland. 



In summer the S. W. wind prevails as to time, but the excess is on the side of 

 the N. E., if the number of miles is considered, but of much less amount than 

 in winter and spring. 



In the second winter station of Capt. Hall's party. Lifeboat Cove or Polaris 

 House, as also in Hayes's Station, Port Foulke, in the vicinity, the N. E. prevail 

 even more than in Polaris Bay in winter and spring. The W. and N. W. are en- 

 tirely wanting. 



In the tables of Professor Coffin, the winds at Eensselaer Harbor, Kane's 

 winter station, were recorded with reference to the magnetic direction. As the 

 magnetic declination is known to be 108° 12' W., I give below the true mean 

 direction of the wind in this locality, and also that recently calculated by Dr. 

 Bessels for Polaris Bay. In the Map, PI. 2, the true direction is given. 



Rensselaer Harbor. 



By Honrs. 



S. 15° E. 



By Milee. 



s. sr E. 



Mean direction. 



N. 38° E. 



Eate of Progress. 

 Miles. 



6279 



S. 1° W. 



S. 36° E. 



S. 2° W. 



1828 



N. T8° E. 



S. 86° E. 



N. 26° B. 



2685 



N. 65° E. 



N. 63° E. 



N. 21° E. 



4394 



S. 86= E. 



S. 89° E. 



N. 40° E. 



11,392 



Spring 



Summer 



Autumn 



Winter 



Year 



The observations of Rensselaer Bay are thus shown to agree, to a considerable 

 extent, with those of the surrounding stations. The winds are more easterly than 

 at Polaris Bay at all seasons, and do not vary as much as at that station, the 

 difference between winter and summer being only 91° instead of 161°. See Map, 

 PI. 2. 



The Danish settlements of Northern and Southern Greenland (all on the west 

 coast of the island), Upernavik, Jacobshavn, and Godthaab, have largely prevailing 

 east winds (from the land) in winter, and west winds (from the sea) in summer. 

 As the force of the winds has not been accurately ascertained, we cannot say whether 

 the N. E. are much stronger than the East, as in Polaris Bay. In the summer 

 the rocky surface of the interior (as Greenland is not all covered with ice) is 

 highly heated by the sun, it draws in the air from the colder sea, which is 

 cooled by the large number of icebergs floating southward. 



We know much less about Eastern Greenland, the country being entirely 

 uninhabited. Yet the 2d German polar expedition having passed a year near 

 Sabine Island, 75° L. N., near the coast, we are able to say that the prevailing 

 winds are N., especially in spring, autumn, and winter, while S. winds are nearly 

 as frequent as N. in summer. The N. prevail here to a less degree than the N. E. 

 at Lifeboat Cove and Port Foulke ; but it would be rash to decide from so short 

 a period and so foAV observations that the polar winds are really less prevailing in 

 the east than in the west of Northern Greenland. The eastern coast of the island 



