USES OF THE SUGAR. 49 



the development of which begins with those substances, 

 with the production of which the life of an ordinary 

 vegetable ends. As soon as the latter has borne seed, 

 it dies, or a period of its life comes to a termination. 



In that endless series of compounds, which begins 

 with carbonic acid, ammonia, and water, the sources of 

 the nutrition of vegetables, and includes the most com- 

 plex constituents of the animal brain, there is no blank, 

 no interruption. The first substance capable of afford- 

 ing nutriment to animals is the last product of the crea- 

 tive energy of vegetables. 



The substance of cellular tissue and of membranes, 

 of the brain and nerves, these the vegetable cannot 

 produce. 



The seemingly miraculous in the productive agency 

 of vegetables disappears in a great degree, when we 

 reflect that the production of the constituents of blood 

 cannot appear more surprising than the occurrence of 

 the fat of beef and mutton in cocoa beans, of human 

 fat in olive oil, of the principal ingredient of butter 

 in palm oil, and of horse fat and train oil in certain oily 

 seeds. 



X. While the preceding considerations leave little or 

 no doubt as to the way in which the increase of mass in 

 an animal, that is, its growth, is carried on, there is yet 

 to be resolved a most important question, namely, that 

 of the function performed in the animal system by sub- 

 stances containing no nitrogen, such as sugar, starch, 

 gum, pectine, &c. 



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