METEOROLOGY 



An important characteristic of Antarctica is the cold 

 summers, with the monthly mean rarely above freezing- 

 point. The diagram brings out the close approximation 

 (within 10°) of all the means recorded for December and 

 January, from regions so far apart in latitude as the 

 wintering stations of the Discovery and the Scotia, 



NOTE ON THERMOMETERS FOR POLAR 



WORK 



By JAMES MURRAY 



For work in regions where temperatures below the 

 freezing point of mercury are to be expected it is custom- 

 ary to trust entirely to spirit thermometers. We had 

 reason to regret doing so. Whatever may be their be- 

 haviour in temperate climates, in polar regions the error 

 of the spirit thermometers is apt to fluctuate in a 

 puzzhng and irritating manner, especially in thermometers 

 which have to be carried about from place to place. 



For example, several thermometers were tested in the 

 sea in winter, when the temperature was just a small 

 fraction above the freezing-point of sea water. They 

 showed errors varying from one or two to many degrees. 

 When tested immediately afterwards in water from melt- 

 ing fresh- water ice, they read quite correctly, that is to say, 

 they showed errors no greater than those indicated on the 

 Kew certificates. 



To make corrections in the readings only for the cer- 

 tified error would be most misleading. To attempt to 

 restore the thermometers by getting the displaced spirit 

 back into the column before beginning a series of obser- 

 vations was of no avail, as the thermometers might go 

 wrong at any moment. 



The only means of giving the readings of spirit ther- 



Vol. II.— 27 417 



