xl INTRODUCTION. 



control. We are told by some authorities on alpine 

 plants, that the failures so commonly experienced in their 

 culture are due to the use of improper soils, mistaken 

 methods of management, and faultily-constructed rock- 

 work. There is some truth in this conclusion in some 

 cases, perhaps, but they are few that can be satisfactorily 

 explained on these grounds. The more important and 

 less controllable influences of a peculiar climate, to which 

 such mere terrestrial conditions are quite subordinate, are 

 either overlooked or ignored in that view of the case. It 

 has been generally admitted by the cultivators of alpine 

 plants, that the difficulties they have had to contend with 

 in the case of the more unmanageable species were at- 

 mospheric, not terrestrial, and that their requirements in 

 the latter respect are the most simple and least liable to 

 be misunderstood of all classes of cultivated plants ; and 

 this view has the merit of harmony with the natural laws 

 which govern the distribution of plants on the earth, as 

 well as with the teachings of experience gathered from 

 the failures and successes which attend the cultivation 

 of plants from all climates. The terrestrial conditions 

 under which they exist in their own wild homes are not 

 uncommon In other regions, and occur pretty frequently 

 in our own land. The beetling crags, moist rocky 

 chasms and fissures, and stony wastes of the Alps, are 

 repeated again and again, in every latitude and at every 

 elevation ; but the gems of the alpine flora do not be- 

 deck them everywhere. And the soil of the alpine re- 

 gions is the simplest of all soils : it Is the ground and 

 battered fragments of the rocks which form the base of 

 all alluvial earth, and Is not peculiar to the Alps, but 

 may be found at the lowest elevations, In as simple a 



