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placing seeds in an atmosphere of nitrogen or hydrogen, 

 when they fail to germinate. 



Seeds germinate more rapidly in shade than in light, and 

 the process is materially influenced by the chemical rays, for 

 while blue light accelerates, yellow rays retard it. The 

 decomposition of carbon is also due to the action of light, 

 and hence it is necessary for the formation of wood and 

 chlorophyl ; a due balance of the chemical and luminous rays 

 is also required for the proper development of flowers and 

 perfection of fruit. Thus you see how nicely adapted are 

 the operations of nature to the co-existing external conditions 

 of the world around : the seeds have laid dormant all through 

 the long winter, or even stored up for years in the granary, 

 and the embryo bud presents no signs of its existence, yet 

 with the first rush of spring the requisite conditions are at 

 hand, the earth is saturated with moisture, the sun with as 

 yet a low elevation imparts sufiicient heat with a moderate 

 supply of light ; but with the full blaze of summer power 

 the flowers attain full development of form and hue, to 

 pass under the calorific and chemical forces of autumn into 

 ripened fruit, again to lie dormant for the winter. 



The first alteration set up in the seed is in the nitrogenized 

 matter, diastase being formed, which acts as a ferment, and 

 the starch is converted into dextrine and grape sugar, and 

 thus rendered soluble and capable of assimilation ; carbonic 

 acid is also evolved from combination of oxygen with the 

 carbon of the seed, and as in all other cases of chemical 

 action, heat is at the same time produced. 



Numerous experiments and theories have been devised to 

 explain the cause of the constant downward growth of the 

 radicle and upward growth of the plumule, but none are 

 satisfactory ; and we must again fall back on vital force, 

 guided by Divine Intelligence. 



The roots of plants only grow at their apex, and here the 



