100 Dr Latta\s Observations on the 



indicated a temperature of 37° ; on the plain it was 44° ; the difference then 

 was 7% which, even allowing that there was a decrease of only one degree for 

 every 90 yards of ascent, reduces the altitudes from 3000 feet to 1890 feet. 

 Nor can this observation of Mr Scoresby's prove any thing else than that the 

 circle of perpetual frost is not so high as 7791 feet ; for there is a strong pre- 

 sumption that it was about its greatest altitude during our visit ; for, not 

 only was the season much more temperate than is common in Greenland, but 

 the observation was made during the warmest portion of that season, and yet 

 the temperature of the plain was 44° ; the difference between that and freez- 

 ing is 12° ; and though we allow the full complement to every degree of dif- 

 ference, perpetual freezing should be encountered not higher than 3240 feet. 

 No doubt the observation was made at midnight, but the temperature at 

 midnight and mid-day is nearly the same ; and if the warmth near the shore 

 is a good deal dependent on the breeze, the hour of observation is of less import- 

 ance ; and farther, the hill was situated near the sea, where the temperature 

 is evidently higher than inland. The thermometer also was placed among 

 stones on the brow of the hill ; these stones were small fragments of lime- 

 stone, lying on a slope perpendicular to the sun's rays, and which, when they 

 imbibe heat, can retain it long. Hence, the thermometer was probably higher 

 than the temperature at such an elevation should have been. I may also notice, 

 the top and shoulders of this hill were deeply clad with snow, the lower margin 

 of which was in a state of rapid solution ; but, on the hill top it was frozen so 

 hard as to resist impression though leaped upon, which indicated, that, though 

 a thawing temperature had been there, it was not permanent ; and if so on a 

 hill so low, and so exposed to the sea breeze, we may conceive the condition 

 of the mountainous regions in the interior, particularly as the temperature 

 evidently sinks as we recede from the shore. 



Indeed, the solitary evidence of the thermometer can afford no satisfactory 

 indication of the amount of altitude, as the lower regions of our atmosphere 

 are very much under the influence of localities, which, particularly in insular 

 situations, is much circumscribed. Accordingly, though the thermometer 

 usually accompanies the scientific traveller, its movements are seldom ad- 

 duced in testimony of elevation. And we cannot help being a little asto- 

 nished at Mr Scoresby's faith in it, and the conclusions at which, biassed by 

 its indications, he has arrived, when we reflect on the peculiarities of a 

 Greenland atmosphere ; and more especially, since these conclusions are most 

 positively contradicted by every other phenomenon presented to the sense in 

 the dreary scenery of Spitzbergen. Indeed, his calculations are more at va- 

 riance with the enlightened views of modern science than the unphilosophical 

 notions of our forefathers, who fancied, that, as the ground became heated by 

 the sun's rays, it imparted caloric to the stratum of air in contact, which, in its 

 turn, warmed the air above, and the temperature of each superjacent stratum 

 thus depended on the proximity to the source of warmth ; but, since it is now 

 established, that the decrement of caloric depends on the increase of capacity 

 which air acquires by the diminution of density, it is evident, that, until be- 

 yond the reach of the influence of the peculiarities of local situation, the evi- 

 dence of the thermometer is inadmissible, and even then its movements are 

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