58 FOOD OF THE VEGETATING PLANT. CHAP. I. 



mosphere was diminished.* It is obvious, then, 

 that the presence of oxygene is beneficial to the 

 growth of the vegetable,, at least as applied to the 

 root ; because that is the only principle which had 

 access to the root in the last experiment, which 

 had not access to it in the former. 



Branch But oxygene is beneficial to vegetation as applied 

 also to the other parts of the plant as well as to the 

 root. Branches of woody plants taken in the 

 spring, immediately before the expansion of the 

 bud, and enclosed in receivers filled with common 

 air, together with a small quantity of water to 

 supply them with moisture, developed their leaves 

 as if attached to the parent plant. And this de- 

 velopement was effected solely by means of the 

 oxygene contained in the receiver ; for in mediums 

 deprived of oxygene no developement took place.-}- 

 The presence of oxygene therefore is necessary to 

 the developement of the leaves. 



Flower But it is necessary also to the developement of 

 the flower and fruit. The flower-bud will not ex- 

 pand if confined in an atmosphere deprived of 

 oxygene ; nor will the fruit ripen. Flower-buds 

 confined in an atmosphere of pure nitrogene faded 

 without expanding. A bunch of unripe Grapes 

 introduced into a globe of glass which was luted 

 by its orifice to the bough, and exposed to the sun, 

 ripened without effecting any material alteration 

 * Sur la Vcg. chap. iii. sect. vi. f Ibid. sect. viii. 



