885 



higher mountains would form an extremely valiiable contribution 

 to meteorology and to plant-ecology. 



d. Movements of the air (ivind). The Færoes have earned 

 a well-deserved reputation for their stormy chmate. 



The mean records show that at Thorshavn only 12 p. cent p. 

 ann. of the days are calm, the remaining 88 p. cent have some wind, 

 frequently a stiff breeze. During the winter-season one in four or 

 five of the soutliwesterly winds becomes a gale or storm, but in 

 summer-time only one in thirty does so. If the strength of the wind 

 be expressed by a scaleofO — 6, then the average figures are 2,o — 2,2 

 in winter, and 1,3 — 1,5 in summer. The winds blow in nearly 

 equal proportions from all points of the compass; though there is 

 some difference in the frequency, in that they are oftenest S. W. 

 and W., N. and N. E. coming next. There is, however, this great 

 difference between the two groups: the former bring heat and 

 moisture, whereas the northerly winds bring cold and little moisture 

 (cfr. M. Knudsen 1900). 



The great influence of the wind on vegetation (mainly as a 

 desiccating agent, but also as a mechanical one), is a well known 

 faet emphasized in the case of northern countries by many bota- 

 nists, particularly E. Warming, N. Hartz (1895), O. Kihlman 

 and more recently by Adolf Hansen. The elfects of the wind are 

 very marked in many piaces on the Færoes. One characteristic type 

 of vegetation, primarily determined by the wind, occurs in its most 

 typical form on the so-called »Eider« (see Fig. 167). These valley- 

 like depressions extending across the istands are swept by winds 

 of such strength, that at times it is impossible to maintain an up- 

 right position. All piants there are dwarfed to such a degree, that 

 they form a closely shorn green sward in which the flowers open 

 amongst the leaves instead of rising some distance above, as under 

 ordinary conditions. As an instance there is in a sward of this 

 kind at Vaag on Sydero an abundance of Lijchnis flos ciiculi with 

 flowering stems not exceeding 2 — 5 ctm., instead of the usual height 

 of 20—50 ctm. The force of the wind is also indicated by the vege- 

 tation of the summit-plateaux of the mountains. Here the sward 

 of dwarfed piants may be found wilh portions torn up and carried 

 away (Fig. 170). It is even possible by examination to determine 

 for any given place the direction of the strengest wind, from the 

 faet that the vegetation forms strips or elongated patches, the long 

 axis of which is at right angles to the wind. In the case of sum- 



57* 



