294 THE HEIGHT OF THE BARRIER AND THE SOUTH POLAR PLATEAU. 



observations each day) were 29- 62" and 24''F. These observations give the difference in height 

 batween the Pole and the Barrier as 9,170 feet. Taking the height of the Barrier to be 170 

 feet as before, this gives the height of the Pole as 9,340 feet above sea-level ; which is only 

 238 feet higher than the value determined above. Thus it strongly supports our determination, 

 but is still further away from Mohn's determination of 8,051 feet. It will be noticed that 

 this is a determination quite indepjiident of Scott's barometer, and depends only on Amundsen's 

 observations and those of a barometer which was compared with the standard at Cape Evans 

 only a few days later. 



Determination of the height of tJie Pole by simultaneous ohservations of Scott's and Amundsen's 

 Barometers. — On January 12th Scott was in 83" 52' S., i.e., within 68 miles of the Pole, 

 while Amundsen was on the Barrier in 84^ S. This day has been chosen for the comparison 

 because the pressure was very steady both on the plateau and on the Barrier, also Amundsen 

 was then travelling rapidly northwards and if we delay the comparison imtil Scott was at 

 the Pole, Amundsen would then be so far north (in 82^ S.) as to make the comparison 

 less valuable. Scott's position was then 660 feet above the Pole as determined by concordant 

 observations made on the journey to and from the Pole. The observations were : Amundsen 

 2-30 P.M., barometer 28-77", temperature +200''F. ; Scott 1-30 p.m., barometer 19-36*, temper- 

 ature -22°F. These reduced in the usual way give the difference in height between the 

 two positions to be 9,649 feet, deducting the 660 feet which Scott was above the Pole and 

 adding 150 feet for Amundsen's height on the Barrier (according to Mohn) we find the height 

 of the Pole to be 9,104 feet above sea-level. 



This value is only 32 feet different from our main determination and may be considered 

 to support it completely. 



Summing up we have the following independent estimates of the height of the South 

 Pole above sea- level : — 



(1) Mohn's determination from Amundsen's observations 



(2) Our chief determination mainly from Scott's observa- 



tions *......... 



(3) Comparison of Amundsen's barometer at the Pole and 



a barometer on the Barrier ..... 



(4) Comparison of Scott's barometer near the Pole and 



Amundsen's on Barrier ..... 



The mean of the last three determinations is 9,172 feet = 2,796 metres which is probably 

 very near to the true height of the South Pole above mean sea-level. 



The height of the Antarctic Continent. 

 Our knowledge of the land masses within the Antarctic is very limited, it is therefore 

 exceedingly interesting to find that an estimate of their extent can be made from purely 

 meteorological considerations. This has been done by Meinardus who concludes that if land 

 occupies two-thirds of the whole area within the Antarctic Circle its average height must be 

 2,000 ± 200 metres. Such a mass of land is so great that it raises the mean height of 

 the earth's whole surface from 205 to 240 metres, or the mean height of all known land is 

 raised from 700 to 825 metres. Such a result is of great scientific importance. Now that 

 Shackleton's attempt to cross the Antarctic Continent has failed, we are unlikely to obtain 

 confirmation of Meinardus's conclusion from actual exploration for many years to come, hence 

 in the interests of both geodesy and meteorology Meinardus's conclusions need critical dis- 

 cussion. This must b3 my excuse for the following pages. 



* la Volume III will be found the detailed data on which this determination is based, and the height of 

 all the camps. 



