Biographical Memoir of the late Christian Smith. 211 



tbcr. The sun of an almost perpetual day calls forth a multi- 

 tude of leaves and flowers, which would scarcely be expected in 

 so northern a latitude. On the contrary, on the other side of 

 the mountains, the sea always open, moderates the severity of 

 the winter, and the constant winds from the west and south, 

 coming over the ocean, heighten the temperature of the coasts. 

 But they cover them, at the same time, with fogs and clouds, 

 which intercept the genial influence of the sun, and thus permit 

 to the warmth of summer a short duration, and limited effect. 

 Smith shews how much this influence manifests itself, in the 

 productions of vegetation in the diff*erent heights at which 

 trees grow, and the limits of perpetual snow. For these, in 

 fact, are much more determined by the warmth of summer than 

 by the cold of winter ; and hence, when their various heights 

 are ascertained, we gain a pretty accurate knowledge of the 

 state of the valleys and plains below. Smith first ascended 

 Goustafield in Tellemark, the highest mountain in the south of 

 Norway, and found it 5886 Parisian feet high ; and the snow 

 line he ascertained at about 4740. On the great chain which 

 separates Tellemark from Hardanger, the snow line did not 

 reach to 4650 feet ; and on Folge Fonden in Hardanger, which 

 is almost surrounded by arms of the sea, it had sunk so low as 

 4036. A great number of annual plants, however, and such as 

 are able to endure the severity of the winter, but which, at the 

 same time, so soon as the sap has ascended, require uninterrupt- 

 ed warmth, to put forth leaves and flowers, is found on the east 

 side, and wherever the snow line is at a considerable elevation. 

 Such bushes and plants, on the other hand, and all such as re- 

 tain their leaves in winter, or at least as shed them late in the 

 season, but which require no great warmth in summer for their 

 support, flourish especially in the softer and more uniform climate 

 of the sea-coast. The former enjoy the climate of the plains of 

 Russia, the other of the flats of England and Scotland, of which 

 the appearance of the birch affords a very palpable and striking 

 example. Vigorous enough to set the severity of a Siberian 

 winter at defiance, it requires, however, uninterrupted warmth 

 to put forth its leaves ; and when these are unfolded, they are 

 so tender that the slightest return of frost is hurtful, if not alto- 

 gether destructive to the growth of the tree. Hence the climate 



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