PREFACE. 



xiii 



Some trees appear to supply every necessary of 

 life to the inhabitants of the countries where they 

 grow ; such are the Birch and the Fir to the in- 

 habitants of Lapland, Sweden, and Norway ; the 

 Lime to the peasants of Russia ; such is the Aloe 

 in America, the Palm in Asia. 



" The more we study vegetable chemistry in the 

 torrid zone," says Humboldt, " the more we shall 

 discover in some remote spot, but attainable by 

 the trade of Europe, and half-prepared in the 

 organs of plants, products that we believe belong 

 only to the animal kingdom, or which we obtain 

 by processes of art, which, though sure, are often 

 tedious and difficult^." 



He instances the wax afforded by one of the 

 Palms, silk by another, and the nourishing milk of 

 the Palo de vaca, the Butter-tree of Africa. Wax 

 is obtained from other plants, as some species of 

 the Myrica ; and tallow from the Tallow-tree 

 (Croton sebiferum). IViany others might be men- 

 tioned. Some authors have spoken facetiously of 

 Shirt-trees, and Cap-trees. " We saw on the slope 



* Humboldt's Personal Narrative^ vol. \. p. 



