•////•. /7/r,s7( )/.()(,)■ ()/• /'/..I.V'/.S 287 



insoluble ;iiul c.isil)' seen. Now take out the 

 phial and let it stand, well covered, when the 

 chalk in the form of a fine precipitate will be 

 seen at the bottom of the phial. If desired, a 

 second experiment can be made with the same 

 jar b\- lowerini; into it a li;4hted taper; wc shall 

 find it will l;o out owin^- to the presence of the 

 carbon-dioxide ; as this <j^as docs not support 

 combusticjn our li<.jhted taper is quickl}- extin- 

 <^uished. 



W'e can see from these experiments that resjjira- 

 tion ij;ocs on in the L^rowinc;' plant and that this 

 process is independent of chloroph}ll. It is an 

 essential j)art of the life of all plants, and my 

 readers who ma}' perhajjs wonder wh}- it is 

 that two such opposite processes as I have 

 described are both carried on in the plant must 

 remember that in the main the feeding process 

 which depends on sunlii^ht and the presence 

 of chlorophxll is carried on in the day time, 

 wh'Ist respiration is practical!)- counteracted 

 in the daytime b>' the \igorous intake of carbon- 

 dioxide. At nij^ht when the rays of lii^ht cease 

 and no longer enable the plant to '{K:K::i\, the respira- 



