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THE PHYSICS OF THE ARCTIC REGIONS. 



I.— METEOROLOGICAL OBSERVATIONS. 



It will probably be unnecessary to discuss at length the records 

 of all those ordinary observations which have been made by pre- 

 vious expeditions to Polar regions, and which are usually included 

 in the ship's log. 

 These include — 



(1 ) Temperature of the air. 



(2.) Direction and force of the wnnd ; and the weather. 

 (3.) The barometer. 



(4.) The temperature of the sea at the surface. 

 (5.) Latitude and longitude. 

 These observations have generally been made every one or twa 

 hours, instead of every watch. 



In Dr. Hayes' expedition they were made every two hours, but 

 hourly observations were made for part of the winter, and the 

 mean of hourly observations of temperature differed from the bi- 

 hourly mean by less than 0°*04. 



Also in McClintock's expedition the hourly and two-hourly 

 series of observations of the barometer give precisely the same 

 mean. 



Observations have also generally been made for — 

 (6.) The temperature of the sea at different depths. 

 (7.) The specific gravity of sea water. 

 (8.) Tides and currents. 

 There are some few points on the relative temperature of 

 different places, and on the connexion between the temperature 

 and the direction of the wind to which it may be well to draw 

 attention. 



1. Meteorological Observations by Sir Leopold McClintock. 



The meteorological records of McClintock's expedition in the 

 " Fox " are discussed in the fourth number of Meteorological 

 Papers of the Board of Trade, 1 860. 



They are also fully discussed in the " Smithsonian Contributions 

 to Knowledge" (Vol. 13). The following facts relating to this 

 expedition are drawn from these sources or from McClintock's 

 Voyage of the " Fox." 



Temperature, 



" Among the principal features of this Arctic register will be 

 found instances of temperature 48° below zero ; a mercurial column 

 of 31 inches (very nearly) at the sea level ; notices of warm winds 

 not only from the south-eastward, but also from the north-west- 

 ward (in the high latitude of 74°), and of several cyclones." 



