There is one human quality, the power of enjoyment, which, above all others, we seem to recognize in our plants. It is impossible to look upon the daffodils in a field dancing in the sunlight of an early April day, without feeling that here is the very embodiment of gladness—of the _joie de vivre_; and as the months speed on and flower after flower bursts into life, meeting the renewed glories of the sun, we have before us a roundelay of gaiety and happiness which only quite ceases when the first grip of winter comes to choke and kill the melancholy glory of autumn. Then, when the dahlias hang their stricken heads, and the blue clouds of the Michaelmas daisies fade and shed their seed, we are conscious of the fact that they, too, have their sorrows, though the tragedy of so many has passed unnoticed when rivals, each one more beautiful than the last, have been springing up to take their place. A greater than I am has noticed the pleasure that plants take in the act of living. A friend sends me these lines of Wordsworth’s: “The budding twigs spread out their fan To catch the breezy air; And I must think, do all I can, That there was pleasure there.” And so we linger on in our Veluvana until the sun is setting in the west. There is an end of light and heat for this day, and the plants, like the birds, must sleep and even dream, if Keats be right.[18] Theirs is perhaps not the sleep which we know, but nothing is more certain than the change which they undergo in darkness. In some plants the leaflets curl downwards, in others upwards; in many the flowers close altogether, and are folded almost as they were when buds. But all green plants show one phenomenon. Whereas under light the leaves take up the air in the little mouths on the underside of their leaves, and after working up the carbonic-acid gas into carbon for the building of their stems and branches, return the rest in the shape of pure oxygen, purifying and sweetening the air; when night comes the process is reversed. Then they retain the oxygen and exhale carbonic-acid gas only, and that is why careful nurses, though they may not know the reason, turn plants out of a sick-room when the night comes on. It has been calculated that of those little stomates on the underside of a beech leaf, little kitchens or laboratories in which the tree prepares its food, there are no fewer than a million. Yes, the plants must sleep—all save certain disreputable night-blooms, which, like owls and bats and witches, hate the light and haunt the darkness. In a few hours the first glimmer of dawn will break; the rosy-fingered goddess will rouse her choir of birds, and they, with their morning hymn, will awaken the trees and the flowers; the blessed dew will fall, distilling the sweet scents of woodland and gardenland, and the joy of the world and of the plants will spring into the birth of a day.