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closes A and E and opens F the measured baryta water in D will flow 

 into the Pettenkofer tube G. This outflow from D will cause the baryta 

 water in the Erlenmeyer flask M to rise in the pipette I. It goes without 

 saying- that for convenience the capacity of D and I should be equal. 

 Next close F and H and open E and J. The air will then enter E when 

 the CO:; will be removed by the soda lime in before entering I through 

 K. This will allow the measured baryta water in I to flow out of J 

 into a suitable vessel for titration. In this way the baryta water meas- 

 ured into G, through which CO- is to be passed, furnishes the power in 

 a convenient way for filling and accurately measuring an equal amount 

 in I, through which the COi; of respiring plants is passed for comparison. 



