HOW THE ROOT LIFTS WATER 89 
To start the experiment to show root pressure. With 
the knife cut off the stem squarely near the ground, 
as shown in Fig. 124. Slip one end of the rubber 
tubing over the end of the stem and tie it tightly with 
the wrapping cord. Then pour in a small quantity of 
water to keep the end of the stem moist at the start. 
Insert one end of the glass tubing in the other end of 

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Fic. 125. The materials for setting up the apparatus to show root pressure. 
the rubber tube, tie it tightly, and then bind the glass 
tubing to the stake to hold it upright. The experiment 
must be made in a room in which the temperature is 
suitable for growth. 
The result of the experiment. In a few hours the 
water will be seen rising in the glass tube. This will 
continue for a day or two, and perhaps for a longer 
time. The soil in the pot should be watered just as if 
the entire plant were growing. Observations on the 
