464 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 



and have been sufficiently prolonged and accurate enough to establish 

 the present general characteristics of the south polar climate. These 

 results have already furnished interesting comparisons with what 

 we know of the boreal region. We would especially seek now an 

 explanation of the glacial phenomena so peculiar to the Antarctic 

 and information concerning the organic life, which is altogether pre- 

 carious or remarkabl}'^ specialized. 



Previous to 1898 the most southerly meteorological stations in 

 the world, those at Ushuaia and on the States Isles (lat. 54° 23' S.), 

 had furnished reports only concerning the Cape Horn region. The 

 observations made by the latest Antarctic expeditions, the most ex- 

 tended being the series of a year, by the Antarctic at South Georgia, 

 have greatly increased this data. Even with respect to the ice-cov- 

 ered region our knowledge has been limited to isolated statements, 

 which it was difficult to consider collectively with advantage. It 

 may be said, however, that studies made by the last expeditions have 

 enriched the geography of the region with a complete new chapter." 



Barometric observations have, first of all, demolished the hy- 

 pothesis according to which, besides a zone of disturbances varying 

 from latitude G0° to latitude 70° S., the prevailing rule in the Ant- 

 arctic would be turbulent winds from the west, verging toward a 

 permanent austral cyclone. The existence of these winds, due to 

 the extension of the great currents of terrestrial rotation from west 

 to east, south of the temperate austral zone, had been generally 

 acknowledged, but this supposition can not be reconciled with that 

 of an austral icy pole. The observations have, on the contrary, 

 shown that the pressure, although very low as an average, does not 

 regularly diminish toward the south, and differs little from the 

 average of 746 mm. at Cape Horn. 



The reductions made at Snow Hill (lat. 64° 22' S.) at 0° and at sea 

 level give a result of 740 mm. At Port Charcot (lat. 65° 04' S.) the 

 corresponding value was 744.87 mm., almost exactly the same as that 

 obtained by the Belgica during her drift (744.7). The meteorologist 

 of the Francais^ M. Rey, only once, in April, observed a maximum 

 somewhat greater, at 760 mm.^ The instruments on the Gauss re- 

 corded, below the polar circle, a mean of 740 mm. Finally, the read- 

 ings made at Cape Adare, the southernmost of the observations 

 taken, show 738.5 mm. In West Antarctica, however, the mini- 



« It would be necessary to read tlie descriptions of tlie voyage to get an idea 

 of the tenacity and courage devoted to these observations. At Port Charcot 

 the readings of the instruments w&ve punctually revised, even during the night 

 and through all kinds of weather. During the Belgica drift the readings were 

 made several times during the day, on the footbridge, etc. 



^Doctor Charcot: Op. cit, p. 351. 



