96 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 70 



In field 40° to 49° west longitude, plate 42, the temperature of 

 the air in February, 1903, was more than double as much below the 

 normal as the surface of the ocean was under its normal value for 

 this month. In March-April, 1903, the air temperature was some- 

 what farther below the normal than the surface temperature. In 

 February, 1904, the difference between the surface temperature and 

 the air temperature was not as great as in February, 1903, but 

 greater than it was in March- April, 1903. In all three months, it was 

 greater than normal. In March-April, 1904, on the other hand, 

 the difference between surface temperature and air temperature 

 was less than normal. In this field therefore we cannot say that the 

 relations point to the view that the temperature variations were 

 primarily caused by changes in the temperature of the water-masses 

 brought in by ocean currents. 



In field 30° to 39° west longitude (pi. 42) the difference between 

 the surface temperature and the air temperature in February, 1903, 

 was normal, in March-April, 1903, it was greater than normal, and 

 in February, 1904, it was considerably greater than normal. On 

 the other hand in March-April, 1904, it was less than normal. 



In field 20° to 29° west longitude (pi. 43) in February, 1903, the 

 difference between the surface temperature and the air temperature 

 was less than normal, in March-April, 1903, somewhat greater than 

 normal, and February, 1904, considerably greater than normal, and 

 in March-April somewhat less than normal. We have here there- 

 fore the same run as in the 10° longitude field 30° to 39° west 

 longitude and that appears scarcely to favor the view that changes 

 in the temperature depend primarily on the variations of tempera- 

 ture of the water-masses in the ocean current. 



In field 10° to 19° west longitude (pi. 43) in February, 1903, the 

 difference between surface temperature and air temperature was 

 considerably less than normal, but here there was a secondary maxi- 

 mum in the surface temperature. In March-April, 1903, the dif- 

 ference between the surface temperature and the air temperature 

 was greater than normal, February, 1904, it was greater, and in 

 March-April somewhat less than normal. Of this field we can 

 therefore say that the February curves indicate that the variations 

 in the surface temperature and the air temperature were not pri- 

 marily due to temperature changes of the masses of water brought 

 on by the ocean currents. 



If we consider now the relation between surface temperature and 

 air temperature in all the fields which we have investigated taken 



