INFLUENCE OF AIR UPON FRUITS. 87 



as the leaves do, when acted upon by the solar rays, the 

 carbonic acid of the atmosphere into carbon and oxygen ; 

 the fruits unite the oxygen of the atmosphere with their 

 own carbon, for the formation of carbonic acid ; so that, 

 in the sun, as in the shade, they absorb oxygen, and trans- 

 pire carbonic acid. 



M. Berard obtained the same rQsults when his experi- 

 ments were performed upon fruits still adhering to the tree, 

 and which were in full vegetation. 



The ripening of fruits appeared to M, Berard to be per- 

 formed by the subtraction of their carbon, through the 

 assistance of the oxygen of the air by which they were 

 surrounded. When this subtraction is in any way pre- 

 vented, the fruit withers and dies. 



When a vacuum is produced in receivers containing the 

 fruits; or when these fruits are surrounded by an atmo- 

 sphere of hydrogen, of azote, or of carbonic acid, they 

 disengage at first a fimali quantity of carbonic acid, bat 

 the quantity of it diminishes sensibly, and ceases altogether 

 towards the third or fourth day. 



In every instance, green fruits remained a long time 

 without undergoing any change ; they made no advance 

 towards ripening, but continued stationary ; resuming, 

 however, their natural action, when, at the end of several 

 days, they were placed in a situation in which they could 

 absorb oxygen, and transpire carbonic acid. 



When fruits are ripe they continue to absorb oxygen, 

 and to form carbonic acid by the union of it with a portion 

 of their carbon ; they likewise furnish a great quantity of 

 this acid, which is produced by the combination of their 

 own elements. 



The observations made by M. Berard upon fruits, at 

 different stages of maturity, show that the same principles 

 are found in them at various periods, but combined in 

 unlike proportions. I will here cite only one of these 

 analyses. 



Apricots, very green. More advanced. Ripe. 



Animal matter .... 0.76 0.34 0.17 



Green coloring matter . . 0.04 0.03 0.10 



Woody substance . . . 3.61 2.53 1.86 



Oum 410 4.47 5.12 



Sugar . . . some appearances, 8.64 16.48 



Malic acid ..... 2.10 2.30 1.80 



Lime a little. a little, a little. 



Water 89.39 84.49 47.84 



