|54« OI * THE NATURALIZATION OF FLANTS. 



The plants of And there is a little doubt but many plants of Chili, and even 

 elevated tropical ( j 10 r e wn j c h g rovv yvithifl the tropics, when found near the ele- 

 endure the cold vation of perpetual froft, would bear the cold of Spitzbergen ; 

 of the higher f or on the tops of mountains are found the plants of the plains 

 of more" northern latitudes. Thus is the falix herbacea of 

 Lapland and Spitzbergen found on the lops of Mourne moun- 

 tains at about the elevation of 2,500 feet. On the Serra of 

 Madeira, latitude 32°, 38', and elevated 5,162 feet, is found 

 the erica arborea, of the neighbourhood of Genoa, latitude 

 44°, 25' *. Therefore as the temperature which prevails at 

 the elevation of 5,162 feet, in latitude 32°, is found nearly to 

 correfpond with that of 51° north : the erica arborea, which 

 grows at that elevation in latitude 32°, will find a climate 

 fuited to its nature in latitude 51° f. But as the before men- 

 tioned plants have a confiderable range of latitude, it may be 

 cultivated farther north when the foil and lituation are favour- 

 able. At James Holmes's, Efq. on the eaftern fliore of Car- 

 rickfergus Bay, four miles nortij of Belfaft, there is a plant in 

 the greateit vigour at the prefent time (July 1799) which has 

 now flood uninjured three as fevere winters as Ireland ever 

 experienced, viz. 1794, 5, 1797, 8, and 1798, 9%. 



The lituation is however favourable, being again ft a weftern 



wall facing the fea, and well (heltered by diftant trees from 



ftrong winds. And in the neighbourhood of the fea I have 



little doubt but it would grow lull farther north. 



The fea air is The fea air has generally been reckoned a powerful obftaclc 



affirmed to be no to j ]ave p l an t a tions on its fliores. But many obfervations hav< 

 obftacle to plan- r ... • , , , . , 



tations; but that convinced me that it is the wind alone which prevents th< 

 the open expo- growth of trees on the (bores of the fea. Aud that on a large 

 pernicious. plain, where the winds are unimpeded in their courfe, the 



fame difficulty of raifing plantations as on the margin of the 



ocean will be experienced. 



' * See Sketch of a Tour on the Continent, by J. E. Smith' 

 M.D. F.R.S. &c. page 200, Vol. I. 



f On dividing 15,577, the height of perpetual froft at th< 

 equator, by the difference of the temperature ahove and below, il 

 is found that every 299 feet of elevation lefltn heat 1°, and on di- 

 viding 5,162 feet by 299, we have 17°, which fubtracted from 

 mean annual temperature of latitude 32°, give 52, for the Sen 

 bf Madeira, correfponding with the latitude 51° (1.) 



X See Kirwan's table of mean annual temperatures. 



