But it is especially striking that menstrual blood's effects are linked to the ideas of cream going sour, mayonnaise that does not take, fermentation, and decomposition; it is also claimed that it is apt to cause fragile objects to break; to spring violin and harp strings; but above all it influences organic substances that are midway between matter and life; this is less because it is blood than because it emanates from genital organs; even without knowing its exact function, people understood it to be linked to the germination of life: