FURTHER CHANGES IN THE SAP. 



195 



CHAPTER XXXIII. 



FURTHER CHANGES IN THE SAP. 



Fig. 



172. Inflorescence and leaf of Dock 

 (JKumex) ; d, magnified petal. 



WE will provide 

 ourselves with a 

 common pickle 

 jar, and about an 

 inch of a small 

 candle or wax- 

 taper bound on to 

 a bit of wire a 

 little longer than 

 the jar, and bend 

 the wire so that 

 you can easily 

 hold the candle 

 inside and close 

 to the bottom of 



So now I will tell you a little about what takes 

 place when the plant takes in its food from the 

 atmosphere (p. 192). There is a gas in the atmos- 

 phere which is called carbonic acid gas, or carbon 



