The faculty of vision among spirits is a property inherent in their nature, and which resides in their whole being, as light resides in every part of a luminous body. It is a sort of a universal lucidity, which extends to everything, which embraces at one time space and things, and in relation to which darkness or material obstacles have no existence. And a moment's reflection shows that this must necessarily be the case. In the human being, sight being produced by the play of an organ acted upon by light, it follows that, without light, man finds himself in darkness; but the faculty of vision being an attribute of the spirit himself, independentely of any exterior agent, spirit-sight is independent of light. Spirits see more distinctly than mankind, for their sight penetrates what his cannot. They are also able to perceive and hear sounds that mankind with his obtuse senses cannot hear, as all the percepted faculties of a spirit are attributes of its nature forming part of its being. When man is encumbered with a physical body his sense of perception reach only through the channels of his physical sense organs.

Spirits of higher orders see-and hear only what they choose to, but evil spirits are compelled to see and hear, often against their will,- whatever may be useful for their amelioration. Spirits are also affected by music, but there is no comparison with the music of the celestial realms, the harmony of which nothing on the earth plane can compare. The one in comparison with the other is crude and the melodies of spirit life are one of perfect harmony. Earth-bound spirits, however, take great pleasure in hearing the music that is made by the hand of man, because they have not yet been able to appreciate anything more sublime. Music has great charms for spirits and is one of the best means of invocation, owing to the great development of their sensitive organs. Spirits do not experience our physical ailments and sufferings, as they know them, because they have undergone them, but they do not have to experience them materially: they are spirits. Neither do spirits experience fatigue and the need of rest. "They cannot feel fatigue as you understand it, and consequently they have no need of your corporeal rest, because they have no organs whose strength requires to be restored. But a spirit may be said to take rest, inasmuch as he is not constantly in a state of activity.

He .does not act materially; his action is altogether intellectual, and his resting is altogether moral; that is to say, that there are moments when his thoughts become less active and is no longer directed to any special object, and this constitutes for him a state which is really one of repose, but a kind of repose which cannot be likened to that of the body. The sort of fatigue which may be felt by spirits is proportionate to their inferiority; for the higher their degree of elevation the less is their need of rest.