water; and thus, it follows that, as the extreme parts of bodies in the water are not dry, the water, with which their extremities are covered, must be interposed between them. If this be true, then it is impossible that one body, when in the water, should be in immediate contact with another; and this holds good for bodies in the air; for the air is in the same relation to bodies in air which water is to bodies in water; but owing to our being in the air, the fact as readily escapes us, as it does aquatic animals, from their being in water, that water is in immediate contact with water. It may then be asked whether there is but one mode of impression for all the senses, or whether it is different for different senses, seeing that taste and touch are acted upon by contact, and the other senses from a distance? But yet this is a seeming difference only, for we perceive the hard and the soft, as we do the odorous, the sonorous, and the visible, through media; with this difference, that the former impressions are made by objects close to, and the latter by objects at a distance from us. On which account, as we perceive all things through a medium, the medium, in the case of bodies close to us, escapes our attention; but if, as we have already said, we could be sensible of all tangible impressions through a membraneous substance, without our being conscious of their having been so transmitted, we should then be situated as we now are, when in water or air;
