150 THE WONDERS OF VEGETATION. 



erses with impunity this deadly valley, since these 

 choking vapors do not reach to the height of his head. 

 Just as the oppression felt in ascending the Himalaya 

 to the height of 15,000 or 16,000 feet, was attributed 

 by the natives to the poisonous emanations of certain 

 herbs, so the terrible phenomena of the Valley of Death 

 also were formerly charged to the exhalations of the 

 upas-tree, and assumed all the more formidable pro- 

 portions in the mind of credulous natives and ig- 

 norant travellers, as no antidote has yet been dis- 

 covered. 



We do not envy the inhabitants of the tropics 

 their cow-tree, and, content with the gift of useful 

 caoutchouc, we readily give up all the rest of the luxu- 

 riant vegetation of those countries, which combine 

 such terrors with all their beauties. As yet no anti- 

 dote known is able to counteract the effects of any of 

 these poisons, which as so many dismal enigmas 

 threaten the human race. They confirm the saying 

 that the brilliant light of tropical nature necessitates 

 equally dark shadows, and that more than one formi- 

 dable dragon as yet guards the entrance of these gar- 

 dens of the Hesperides. 



