G6 SiLVA AMERICANA. 



and bursting its integuments, and at length fixing itself in the soil : 

 the plumelet next unfolds its parts, developing the rudiments of 

 the leaf, branch and trunk ; and finally the seminal leaves decay 

 and drop off ; and the embryo has been converted into a plant 

 capable of abstracting immediately from the soil or atmosphere 

 the nourishment necessary to its future growth. 



Food of Plants. 



It is of the utmost consequence to determine what is the food 

 of plants. Upon that question philosophers have widely differed. 

 From a variety of experiments, accurately conducted, we are led 

 to believe that all vegetables, from the hyssop upon the wall, to 

 the cedar of Lebanon, receive their principal nourishment from 

 oily particles incorporated with water, by means of gasses, 

 vegetable extracts, salts, earths and manures. Until oil is 'made 

 miscible, it is unable to enter the radical vessels of vegetables ; 

 and on that account Providence has bountifully supplied all 

 natural soils with chalky or other absorbent particles. We say 

 natural soils, for those which have been assisted by art are full of 

 materials for that purpose ; such as lime, marl, soap, ashes and 

 the volatile alkaline salt of putrid matter. It may be asked, 

 whence do natural soils receive their oily particles ? We answer 

 the air supplies them. During the summer months, the atmos- 

 phere is full of exhalations arising from the steam of putrid 

 substances, the perspiration of animals and smoke. Every 

 shower brings down these putrescent and oleaginous particles for 

 the nourishment of plants. Of these particles some fall into the 

 sea, where they probably serve for the nourishment of the fuci, 

 and other submarine plants. They are, however, but seemingly 

 lost, as the fishes taken from the sea, and the weeds thrown upon 

 the beach, restore them again under a different form. 



The ingenious Mr. Tull, and others, contend that earth- is the 

 food of plants. If so, all soils equally tilled would prove equally 

 prolific. The increased fertility of a well pulverized soil, induced 

 him to imagine that the plough could so minutely divide the 

 particles of earth, as to fit them for entering into the roots of 



