compelled. _That_ flits upon an orbit elliptically or parabolically or
hyperbolically curved, keeping no man knows what trysts with Time.

It seems fit that Shelley and the author of the _Imitation_ should both
have been keen and simple enough to perceive these flights, and to guess
at the order of this periodicity. Both souls were in close touch with
the spirits of their several worlds, and no deliberate human rules, no
infractions of the liberty and law of the universal movement, kept from
them the knowledge of recurrences. _Eppur si muove_. They knew that
presence does not exist without absence; they knew that what is just upon
its flight of farewell is already on its long path of return. They knew
that what is approaching to the very touch is hastening towards
departure. 'O wind,' cried Shelley, in autumn,

'O wind,
If winter comes, can spring be far behind?'

They knew that the flux is equal to the reflux; that to interrupt with
unlawful recurrences, out of time, is to weaken the impulse of onset and
retreat; the sweep and impetus of movement. To live in constant efforts
after an equal life, whether the equality be sought in mental production,
or in spiritual sweetness, or in the joy of the senses, is to live
without either rest or full activity. The souls of certain of the
saints, being singularly simple and single, have been in the most
complete subjection to the law of periodicity. Ecstasy and desolation
visited them by seasons. They endured, during spaces of vacant time, the
interior loss of all for which they had sacrificed the world. They
rejoiced in the uncovenanted beatitude of sweetness alighting in their
hearts. Like them are the poets whom, three times or ten times in the
course of a long life, the Muse has approached, touched, and forsaken.