WONDERS OF PLANT GROWTH. 81 



it corresponds in structure with the huge oak which grows by 

 the stream and overshadows it with its branches. The plant 

 that adheres to the rock consists of a single cell, but that cell is 

 as perfect and beautiful as any of those which make up the 

 structure of the oak. The tree is but an aggregation of cells, — 

 cells piled upon cells ; and the work that is carried on within 

 them is no more complex than that which goes on in the work- 

 shop of the humble unicellular plant. 



It is with a choice of terms that we designate the cell as the 

 workshop of the plant, in which the materials that enter into its 

 organization are elaborated and fitted to aid in the increase of 

 its substance. The nature of the food which is manipulated 

 within the cell is indeed peculiar, inasmuch as plants gather 

 together the waste products of men and animals, and again fit 

 them for the use of higher organisms. Plant- food is oxidized 

 food — food which it is impossible for animals to assimilate ; and 

 the plant, in all its functions and in the objects of its growth, 

 manifestly occupies an intermediate position between ourselves 

 and the insensible rocks. This is absolutely essential to the 

 existence of man upon the earth. Of all the functions of plants, 

 the most remarkable are connected with or related to the solar 

 rays, for they possess the power of utilizing the sun's heat in a 

 way which enables them to pull apart, as it were, some of the 

 most complex and refractory compounds known to modern 

 chemistry. The most tiny, feeble leaf, or blade of grass, has a 

 power in chemical decomposition greater by far than is pos- 

 sessed by Liebig, Boussingault, or any of the great experiment- 

 ers of the age. The separating in silence, in the quiet of the 

 meadows, by organisms so frail that we can crush them between 

 the thumb and finger, of a compound so fixed as carbonic acid, 

 is one of the marvels in nature which puzzles and confounds 

 the philosopher, and leads him to bow in humility before the 

 God of nature, whose power so infinitely surpasses that of man. 

 But after all, this analytical power of the plant is no less amaz 

 ing than its synthetical capabilities. The work of tearing apart 

 oxidized bodies is immediately followed by that of rearranging 

 the elements, and forming new compounds still more complex, 

 and into these, as a fixed principle, less oxygen is allowed to 

 enter. The great work of the plant is, to disassociate oxygen 

 from compounds, and thus store 1 up energies which are made 

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