INTRODUCTION. 5 



nig a wide field to the creative powers of his imagination. 

 Impressions change with the varying movements of the mind, 

 and we are led by a happy illusion to believe that we receive 

 from the external world that with which we have ourselves 

 invested it. 



When far from our native country, after a long voyage, we 

 tread for the first time the soil of a tropical land, we experi- 

 ence a certain feeling of surprise and gratification in recog- 

 nising, in the rocks that surround us, the same inclined schistose 

 strata, and the same columnar basalt covered with cellular 

 nmygdaloids, that we had left in Europe, and whose identity 

 of character, in latitudes so widely different, reminds us, that 

 the solidification of the earth's crust is altogether independent 

 of climatic influences. But these rocky masses of schist and of 

 basalt are covered with vegetation of a character with which 

 we are unacquainted, and of a physiognomy wholly unknown 

 to us ; and it is then, amid the colossal and majestic forms of 

 an exotic flora, that we feel how wonderfully the flexibility of 

 our nature fits us to receive new impressions, linked together 

 by a certain secret analogy. We so readily perceive the 

 affinity existing amongst all the forms of organic life, that 

 although the sight of a vegetation similar to that of our 

 native country might at first be most welcome to the eye, as 

 the sweet familiar sounds of our mother tongue are to the ear, 

 we nevertheless, by degrees, and almost imperceptibly, become 

 familiarised with a new home and a new climate. As a true 

 citizen of the world, man everywhere habituates himself to 

 that which surrounds him ; yet fearful, as it were, of breaking 

 the links of association that bind him to the home of his child- 

 hood, the colonist applies to some few plants in a far distant 

 clime the names he had been familiar with in his native land ; 

 and by the mysterious relations existing amongst all types of 

 organisation, the forms of exotic vegetation present them- 

 selves to his mind as nobler and more perfect developments of 

 those he had loved in earlier days. Thus do the spontaneous 

 impressions of the untutored mind lead, like the laborious 

 deductions of cultivated intellect, to the same intimate per- 

 suasion, that one sole and indissoluble chain binds together all 

 nature. 



It may seem a rash attempt to endeavour to separate, into its 

 different elements, the magic powar exercised upon our minds 



