Leeches are worms that live in freshwater environments. The majority feed on blood using two suckers, one at each end of their bodies. In medicine, leeches have been used for bloodletting for thousands of years. This is a process whereby a small amount of blood is removed from the body in the belief that blood is a ‘humour’ that needs to be kept in balance. Removing ‘excess’ blood was thought to bring the body back into balance and so cure a variety of symptoms.
Selling cookies is a major fund-raising activity of the Girl Scouts association. Prizes are offered to the girl who can sell the most. The cookies cannot be bought online, as the selling and interaction with the customer are deemed to be part of the development and experience for the girls involved. The sale of Girl Scout cookies began in the USA with homemade sugar cookies; now several large commercial bakeries produce the cookies. There are set varieties, and the different types have become famous across the United States.
A sundial is a device that tells the time based on the movement of the sun. The flat surface is marked with lines indicating the hours, and a rod or triangular protrusion called a gnomon rises from the centre to create a shadow.