20 COSMOS. 



more widely-diffused cultivation of tropical floras, and the 

 more strongly contrasting opposition of exotic and indigenous 

 forms. Each of these might, owing to their historical rela- 

 tions, he made the object of a widely-extending consideration, 

 but it appears to me more in conformity with the spirit and 

 aim of this work merely to unfold a few leading ideas, in order 

 to remind the reader how differently the aspect of nature has 

 acted on the intellect and feelings of different nations at dif- 

 ferent epochs, and how, at periods characterized by general 

 mental cultivation, the severer forms of science arid the more 

 delicate emanations of fancy have reciprocally striven to infuse 

 their spirit into one another. In order to depict nature in its 

 exalted sublimity, we must not dwell exclusively on its extern- 

 al manifestations, but we must trace its image, reflected in 

 the mind of man, at one time filling the dreamy land of phys- 

 ical myths with forms of grace and beauty, and at another 

 developing the noble germ of artistic creations. 



In limiting myself to the simple consideration of the in- 

 citements to a scientific study of nature, I would not, how- 

 ever, omit calling attention to the fact that impressions arising 

 from apparently accidental circumstances often as is repeat- 

 edly confirmed by experience exercise so powerful an effect 

 on the youthful mind as to determine the whole direction of 

 a man's career through life. The child's pleasure in the form 

 of countries, and of seas and lakes,* as delineated in maps ; 

 the desire to behold southern stars, invisible in our hemis- 

 phere ;f the representation of palms and cedars of Lebanon 

 as depicted in our illustrated Bibles, may all implant in. the 

 mind the first impulse to travel into distant countries. If I 

 might be permitted to instance my own experience, and recall 

 to mind the source from whence sprang my early and fixed 

 desire to visit the land of the tropics, I should name George 

 Forster's Delineations of the South Sea Islands, the pictures 

 of Hodge, which represented the shores of the Ganges, and 

 which I first saw at the house of Warren Hastings, in Lon- 

 don, and a colossal dragon-tree in an old tower of the Botan- 

 ical Garden at Berlin. These objects, which I here instance 

 by way of illustration, belong to the three classes of induce- 



* As the configuration of the countries of Italy, Sicily, and Greece, 

 and of the Caspian and Red Seas. See Relation Histarique du Voy. aux 

 Regions Eqitinoxiales, t. i., p. 208. 

 t Dante, Purg., i., 25-28. 



Goder pareva il ciel di lor fiammelle : 



O setteutrional veclovo sito, 



Poi che private se' di nairar quelle ! 



