With one child stretched across her torso and two on her back, this figure demonstrates the value the Dogon place on having many children. The two children on the mother's back are surely meant to be twins, since their bodies are not merely identical in form but seem fused to imply a single identity.The features of this sculpture are all but obscured by the thick crust of sacrificial materials that cover it. Sacrificial liquids are poured on figurative sculptures and other ritual objects found on personal altars, ancestral altars, in binu sanctuaries dedicated to the "immortal" ancestors, on altars dedicated to Nommo, the first living being, and on ya?pil? altars, which are dedicated to the souls of women who died in pregnancy or childbirth. Many different substances are used for sacrifice, including the blood of chickens, sheep, and goats; millet porridge; mixtures of various fruit and plant juices and pulp with millet flour or flour made from the fruit and seeds of the baobab and yullo (Parkia biglobosa) trees; and concoctions of burned herbs, charcoal, and shea oil or the oil of the sa tree (Lannea acida).These sacrificial materials are vehicles for nyama, the vital force that determines a person's mental and physical well-being and allows a person to continue living. Nyama is found in all living things, including animals and plants, and in supernatural beings as well. Nyama can be liberated from its support and transmitted to another being, for example when an animal is killed or a plant crushed. When a sacrifice is made, the nyama of the sacrificial material strengthens and increases not only the nyama of the spiritual being to whom the sacrifice is offered but also that of the persons who perform the sacrifice. In the Dogon language the work for sacrifice, bulu, is derived from the verb bulo, meaning 'to revivify or resuscitate,' which underscores the positive, life-affirming benefits of the ritual. Although sacrificial materials may obscure the appearance of the sculpture, the ritual of sacrifice puts both the agent and object of the sacrifice in a state of purity, order, freshness, and vitality.