On a white stand to show transpiration which occurs in small plant shoots. The apparatus is submerged and the specimen placed in the tube. When transpiration occurs, the bubble in the capillary moves. A syringe is used to zero the scale. Allows the students to measure transpiration with minimal risk of breakages. The only glass component, the capillary – is mounted on a strong backing plate. Can also be used to measure humidity by connecting a porous pot.