But while it takes days, months, sometimes years to produce a work of art, it may require (the process has been submitted to exact measurement by the stop-watch) not minutes but seconds, to take stock of that work of art in such manner as to carry away its every detail of shape, and to continue dealing with it in memory. The unsuspected part played by memory explains why aesthetic contemplation can be and normally is, an intermittent function alternating with practical doing and thinking. It is in memory, though memory dealing with what we call the present, that we gather up parts into wholes and turn consecutive measurements into simultaneous relations; and it is probably in memory that we deal empathically with shapes, investing their already perceived directions and relations with the remembered qualities of our own activities, aims and moods. And similarly it is thanks to memory that the brief and intermittent acts of aesthetic appreciation are combined into a network of contemplation which intermeshes with our other thoughts and doings, and yet remains different from them, as the restorative functions of life remain different from life's expenditure, although interwoven with them. Every Reader with any habit of self-observation knows how poignant an impression of beauty may be got, as through the window of an express train, in the intermittence of practical business or abstract thinking, nay even in what I have called the _off-beat_ of deepest personal emotion, the very stress of the practical, intellectual or personal instant (for the great happenings of life are measured in seconds!) apparently driving in by contrast, or conveying on its excitement, that irrelevant aesthetic contents of the _off-beat_ of attention. And while the practical or intellectual interest changes, while the personal emotion subsides, that aesthetic impression remains; remains or recurs, united, through every intermittence, by the feeling of identity, that identity which, like _the rising of the mountain,_ is due to the reiterative nature of shape-contemplation: the fragments of melody may be interrupted in our memory by all manner of other thoughts, but they will recur and coalesce, and recurring and coalescing, bring with them the particular mood which their rythms and intervals have awakened in us and awaken once more. That diagrammatic Man on the Hill in reality _thought away_ from the landscape quite as much as his practical and scientific companions; what he did, and they did not, was to think _back_ to it; and think back to it always with the same references of lines and angles, the same relations of directions and impacts, of parts and wholes. And perhaps the restorative, the healing quality of aesthetic contemplation is due, in large part, to the fact that, in the perpetual flux of action and thought, it represents reiteration and therefore stability.