Ofuro, a short, deep Japanese bathtub, often with a seat, in which a person sits upright while soaking in hot water. Bathing in wooden tubs originates from the concept that human beings experience the best possible conditions during gestation. Therefore, the tub is at least 2 feet deep, so that the person's spinal column is completely submerged and the body assumes a fetal position. This simulates the beneficial effects experienced within the uterus.