Appendix] of high Mountains. 



air, it is also affected by the obliquity of the rays of the sun ; and 

 the distribution of vegetables in all Alpine countries, depends 

 principally on these two causes. 



Thus iu the Swiss Alps, and Pyrenees, trees cease to grow at 

 about 2400 or 2500 metres of actual elevation, as they do about 

 the 70th degree of north latitude; and that circle tfcese gigantic 

 vegetables occupy, is divided into several lesser bounds, which 

 have each their peculiar characteristics. At the foot of the 

 mountain we find the Oak: in the middle region the Beech: above 

 these the Fir and Yew succeed, which soon give place to the Pine 

 (Pinus Sylvestris Linn.) Along with this last mentioned tree, in the 

 Swiss Alps, the Larch and Cembro (P inus Cembra Linn.) also irrow 

 wild, which are unknown in the Pyrenees. The Cedar of Lebanon 

 would probably thrive as well on these mountains, as on those of 

 Asia, had it been fixed there ; but such is still the mystery of the 

 original dissemination of vegetables, that Nature seems by turns, 

 indifferent to the similitude of places, or to the distance between 

 them; sometimes bringing together in the same climate, plants 

 of the most distant countries ; and sometimes denying this con- 

 formity of vegetables to regions exactly alike, both in soil and 

 temperature. 



In this zone of trees, the Rhododendron ferrugineum Linn, a little 

 shrub peculiar to the mountains of Europe solely, is very abun- 

 dant. It never descends into the plains, and can hardly be cul- 

 tivated in a garden, demanding its native air, soil, water, nay 

 snows, and even there only occupies particular spots. Nothing 

 is more beautiful when in flower, but nothing is more untractable. 

 In the Pyrenees, it first appears at exactly 1600 metres of eleva- 

 tion, stopping as precisely at 2600 metres, and within these limits, 

 is so abundant and vigorous, that it would be as difficult to ex- 

 tirpate it there, as it is to cultivate it elsewhere.* 



* No shrub is more plentiful, or easily cultivated in the gardens about London, if 



vol. r. * J) 



