or else where any motion or succession is so slow, as that it keeps not pace with the ideas in our minds, or the quickness in which they take their turns, as when any one or more ideas in their ordinary course come into our mind, between those which are offered to the sight by the different perceptible distances of a body in motion, or between sounds or smells following one another, there also the sense of a constant continued succession is lost, and we perceive it not,