How to use a Potometer

Image From: en.wikipedia.org/wiki/Potometer#use

How to Setup 

1. Cut a leafy shoot from a plant and plunge its base into water. This prevents the xylem from taking up any air. Wetting the leaves themselves will alter the rate of transpiration.
2. put the whole of the potometer into the sink. Move it about until all the air bubbles come out.
3. cut the shoot's stem underwater. Put it into the bung.
4. Make sure the tap is closed, then lift the whole apparatus out of the water.
5. Leave the end of the capillary tube out of the water until an air bubble forms then put the end into a beaker of water.

How to use 

1. Set up the conditions of the experiment. changes to lighting (placing the plant in bright light or shadow), wind (directing a fan at the plant), and humidity (placing the plant in a humid chamber) are normal.
2. Let the bubble reach a "zero" point in the tube. 
3. Measure the movement of the bubble at regular intervals and record the results in excel or on paper.