A potometer measures how factors such as light, temperature, humidity, light intensity and wind will affect the rate of transpiration. The main type of potometer is the 'bubble' potometer shown in Figure Figure 6.
Physicians recommended against the practice because they did not want medicines associated with punishment. A heavy dose of castor oil could be used as a humiliating punishment for adults, especially political dissenters. Colonial officials used it in the British Raj (India) to deal with recalcitrant servants. Belgian military officials prescribed heavy doses of castor oil in Belgian Congo as a punishment for being too sick to work.
Castor Oil Uses. Castor oil has traditionally been used as a remedy for treating various skin conditions and infections, relieving constipation, and increasing the health of hair. However, recent studies have shown that castor oil can be used to support the immune system, and an anti-inflammatory agent, antimicrobial agent, and lymphatic stimulant. You can use castor oil in a couple of different ways. Apply it directly to the skin, use it through a castor oil pack, or mix it with other oils to use it as a topical remedy.