1. Calibration of the apparatus is done by determining the capillary rise of deionized water. Add enough water to the bottom of the test tube so that the bottom of the capillary can Install the stopper with the capillary in it and clamp the whole setup so all parts of the apparatus containing water (including the water in the capillary) are immersed in the water bath. The calibration measurements should be done at the beginning, and they do not have to be repeated between measurements of other materials, so long as the same capillary is used and the experiments are done on the same day.