34 COSMOS. 



impressions, loses all distinctness of form, like some distant 

 mountain shrouded from view by a vail of mist, is clearly re- 

 vealed by the light of mind, which, by its scrutiny into the 

 causes of phenomena, learns to resolve and analyze their dif- 

 ferent elements, assigning to each its individual character. 

 Thus, in the sphere of natural investigation, as in poetry and 

 painting, the delineation of that which appeals most strong- 

 ly to the imagination, derives its collective interest from the 

 vivid truthfulness with which the individual features are por- 

 trayed. 



The regions of the torrid zone not only give rise to the 

 most powerful impressions by their organic richness and their 

 abundant fertility, but they likewise afford the inestimable 

 advantage of revealing to man, by the uniformity of the vari- 

 ations of the atmosphere and the development of vital forces, 

 and by the contrasts of climate and vegetation exhibited at 

 different elevations, the invariability of the laws that regulate 

 the course of the heavenly bodies, reflected, as it were, in ter- 

 restrial phenomena. Let us dwell, then, for a few moments, 

 on the proofs of this regularity, which is such that it may be 

 submitted to numerical calculation and computation. 



In the burning plains that rise but little above the level of 

 the sea, reign the families of the banana, the cycas, and the 

 palm, of wliich the number of species comprised in the flora 

 of tropical regions has been so wonderfully increased in the 

 present day by the zeal of botanical travelers. To these 

 groups succeed, in the Alpine valleys, and the humid and 

 shaded clefts on the slopes of the Cordilleras, the tree-ferns, 

 whose thick cylindrical trunks and delicate lace-like foliage 

 stand out in bold relief against the azure of the sky, and the 

 cinchona, from which we derive the febrifuge bark. The 

 medicinal strength of this bark is said to increase in propor- 

 tion to the degree of moisture imparted to the foliage of the 

 tree by the light mists which form the upper surface of the 

 clouds resting over the plains. Every where around, the con- 

 fines of the forest are encircled by broad bands of social plants, 

 as the delicate aralia, the thibaudia, and the myrtle-leaved 

 Andromeda, while the Alpine rose, the magnificent befaria, 

 weaves a purple girdle round the spiry peaks. In the cold 

 regions of the Paramos, which is continually exposed to the 

 fury of storms and winds, we find that flowering shrubs and 

 herbaceous plants, bearing large and variegated blossoms, 

 h^ve given place to monocotyledons, whose slender spikes con- 

 it"*,ute the sole covering of the soil. This is the zone of the 



