78 NUTRIMENT OF FRUIT. 



The food of fruit, employed in its maturation, is derived in part 

 from the atmosphere, but mostly through the leaves, which, after re- 

 ceiving it from the roots, prepare it for the food of the fruit. All cir- 

 cumstances, therefore, which impair the health and action of the roots 

 and leaves affect, in like manner, the fruit. It is necessary, also, that 

 the leaves should be contiguous to the fruit, in order to furnish it 

 readily with its requisite food. Hence it is seen that fruit on naked 

 branches will not grow, and that leaves immediately over the fruit 

 prove of the greatest advantage to it. A full supply of nutriment from 

 these sources is therefore the only assurance of good fruit, however 

 valuable its kind may be. It sometimes happens that an undue ac- 

 cumulation of sap proves injurious to the products of plants, especially 

 tuberous plants. The potato, from this circumstance, is liable to the 

 disease called curl, owing to the inspisated state of the juices. Fruit 

 oftentimes fails to elaborate the juices within it, or receives more 

 water than it passes off through its small pores, and it therefore be- 

 comes watery." But when its stomates readily give off superfluous 

 aqueous particles, it becomes hard and dry. A superabundance of 

 water always retards or prevents ripening. The quality of fruit, de- 

 pends much on the quantity and quality of its juices. It is certain 

 that these undergo a great alteration in the fruit after coming from the 

 leaves, as the juice of the leaves of many species are acrid and even 

 poisonous. Thus the leaves of the peach, the fig, etc., are very dif 

 ferent from the fruit. 



Light and heat have an immediate and very important influence in 

 the maturation of fruit. The valuable qualities of fruits, natives of 

 warm climates, certainly could not be developed in this climate. The 

 production of sugar and many rich flavors are obviously the effect of 

 a bright light and a high temperature, while, under diverse circum- 

 stances, the same fruits become acid and unpalatable. The sweetness 

 of ripe fruits depends on their sugar. This contains much carbon, 

 the superfluous oxygen which formed with it the vegetable acid having 

 been expelled by the action of heat. Besides, vegetable acids, at a 

 high temperature, may enter into combination with gums, starch, etc., 

 and thus form sugar much more readily than at a low temperature. 

 Hence acid fruits become much sweeter by cooking. 



The seeds of fruit, during ripening, attract from it matter for their 

 organization, and serve at the same time to correct some of its quali- 

 ties. They are lodged in and are attached to a soft part of the inte- 

 rior called the placenta, the most absorbent of tissues, and are envel- 

 oped by the parenchyma of the fruit. They are dry when ripe, and 

 their interior is filled with starch, earthy matter, etc. Being enclosed 

 by an indurated envelop, these substances will remain undecomposed 

 and possessed of the vital principle for hundreds and even thousands 

 of years. Melon seeds and rye have germinated when 40 years old, 



