5560. The communities of spirits to which the cartilages and bones correspond are very many. But they are the kind that have very little spiritual life within them, even as very little life is present in the bones when compared with the softer parts which they encompass, such as the skull and bones belonging to the head when compared with both parts of the brain, the medulla oblongata, and the substances within these that belong to the senses, or, for instance, the vertebrae and ribs when compared with the heart and lungs; and so on.