Club-moss spores have been used as a dusting powder in surgery, as baby powder and to treat various skin problems, including eczema and chaffed skin. The spores repeal water so strongly that a hand dusted with them can be dipped into water without becoming wet. However, their use as an anti-absorbent is limited as they are know to irritate mucous membranes. The Carrier used to put club-moss spores to divine the future of the sick people. The spores were dropped into a container of water and if they moved towards the sun, the patient would survive. Club-moss spores are very rich in oil, and they are highly flammable. At one time they were used by photographers and theatre performers as flash powder, giving the effect of lightning on the stage. Because they ignite explosively, club-moss spores were called 'witch's flour'.