I sometimes walk in a large garden where the evening primrose is permitted to grow, but only at the extreme end of the ground, thrust away, as it were, back against the unkept edge with its pretty tangle of thorn, briar, and woodbine, to keep company there with a few straggling poppies, with hollyhock, red and white foxglove, and other coarse and weed-like plants, all together forming a kind of horizon, dappled with colour, to the garden on that side, a suitable background to the delicate, more valued blooms. It has a neglected appearance, its tall straggling stems insufficiently clothed with leaves, leaning away from contact with the hedge; a plant of somewhat melancholy aspect, suggesting to a fanciful mind the image of a maiden originally intended by Nature to be her most perfect type of grace and ethereal loveliness, but who soon outgrew her strength with all beauty of form, and who now wanders abroad, careless of appearances, in a faded flimsy garment, her fair yellow hair dishevelled, her mournful eyes fixed ever on the earth where she will shortly be.

I never pass this weedy, pale-flowered alien without stooping to thrust my nose into first one blossom, then another, and still another, until that organ, like some industrious bee, is thickly powdered with the golden dust. If, after an interval, I find myself once more at the same spot, I repeat this performance with as much care as if it was a kind of religious ceremony it would not be safe to omit; and at all times I am as reluctant to pass without approaching my nose to it, as the great Dr. Johnson was to pass a street-post without touching it with his hand. My motive, however, is not a superstitious one, nor is it merely one of those meaningless habits which men sometimes contract, and of which they are scarcely conscious. When I first knew the evening primrose, where it is both a wild and a garden flower and very common, I did not often smell at it, but was satisfied to inhale its subtle fragrance from the air. And this reminds me that in England it does not perfume the air as it certainly does on the pampas of La Plata, in the early morning in places where it is abundant; here its fragrance, while unchanged in character, has either become less volatile or so diminished in quantity that one is not sensible that the flower possesses a perfume until he approaches his nose to it.

My sole motive in smelling the evening primrose is the pleasure it gives me. This pleasure greatly surpasses that which I receive from other flowers far more famous for their fragrance, for it is in a great degree mental, and is due to association. Why is this pleasure so vivid, so immeasurably greater than the mental pleasure afforded by the sight of the flower? The books tell us that sight, the most important of our senses, is the most intellectual; while smell, the least important, is in man the most emotional sense. This is a very brief statement of the fact; I will now restate it another way and more fully.

I am now holding an evening primrose in my hand. As a fact at this moment I am holding nothing but the pen with which I am writing this chapter; but I am supposing myself back in the garden, and holding the flower that first suggested this train of thought. I turn it about this way and that, and although it pleases it does not delight, does not move me: certainly I do not think very highly of its beauty, although it is beautiful; placed beside the rose, the fuchsia, the azalea, or the lily, it would not attract the eye. But it is a link with the past, it summons vanished scenes to my mind. I recognise that the plant I plucked it from possesses a good deal of adaptiveness, a quality one would scarcely suspect from seeing it only in an English garden. Thus I remember that I first knew it as a garden flower, that it grew large, on a large plant, as here; that on summer evenings I was accustomed to watch its slim, pale, yellow buds unfold, and called it, when speaking in Spanish, by its quaint native name of James of the night, and, in English, primrose simply. I recall with a smile that it was a shock to my childish mind to learn that our primrose was not THE primrose. Then, I remember, came the time when I could ride out over the plain; and it surprised me to discover that this primrose, unlike the four-o’clock and morning-glory, and other evening flowers in our garden, was also a wild flower. I knew it by its unmistakable perfume, but on those plains, where the grass was cropped close, the plant was small, only a few inches high, and the flowers no bigger than buttercups. Afterwards I met with it again in the swampy woods and everglades along the Plata River; and there it grew tall and rank, five or six feet high in some cases, with large flowers that had only a faint perfume. Still later, going on longer expeditions, sometimes with cattle, I found it in extraordinary abundance on the level pampas south of the Salado River; there it was a tall slender plant, grass-like among the tall grasses, with wide open flowers about an inch in diameter, and not more than two or three on each plant. Finally, I remember that on first landing in Patagonia, on a desert part of the coast, the time being a little after day-break, I became conscious of the familiar perfume in the air, and, looking about me, discovered a plant growing on the barren sand not many yards from the sea; there it grew, low and bush-like in form, with stiff horizontal stems and a profusion of small symmetrical flowers.

All this about the plant, and much more, with many scenes and events of the past, are suggested to my mind by the flower in my hand; but while these scenes and events are recalled with pleasure, it is a kind of mental pleasure that we frequently experience, and very slight in degree. But when I approach the flower to my face and inhale its perfume, than a shock of keen pleasure is experienced, and a mental change so great that it is like a miracle. For a space of time so short that if it could be measured it would probably be found to occupy no more than a fraction of a second, I am no longer in an English garden recalling and consciously thinking about that vanished past, but during that brief moment time and space seem annihilated and the past is now. I am again on the grassy pampas, where I have been sleeping very soundly under the stars — would that I could now sleep as soundly under a roof! It is the moment of wakening, when my eyes are just opening to the pure over-arching sky, flushed in its eastern half with tender colour; and at the moment that nature thus reveals itself to my vision in its exquisite morning beauty and freshness, I am sensible of the subtle primrose perfume in the air. The blossoms are all about me, for miles and for leagues on that great level expanse, as if the morning wind had blown them out of that eastern sky and scattered their pale yellow stars in millions over the surface of the tall sere grass.

I do not say that this shock of pleasure I have described, this vivid reproduction of a long-past scene, is experienced each time I smell the flower; it is experienced fully only at long intervals, after weeks and months, when the fragrance is, so to speak, new to me, and afterwards in a lesser degree on each repetition, until the feeling is exhausted. If I continue to smell again and again at the flower, I do it only as a spur to memory; or in a mechanical way, just as a person might always walk along a certain path with his eyes fixed on the ground, remembering that he once on a time dropped some valuable article there, and although he knows that it was lost irrecoverably, he still searches the ground for it.

Other vegetable odours affect me in a similar way, but in a very much fainter degree, except in one or two cases. Thus, the Lombardy poplar was one of the trees I first became acquainted with in childhood, and it has ever since been a pleasure to me to see it; but in spring, when its newly opened leaves give out their peculiar aroma, for a moment, when I first smell it, I am actually a boy again, among the tall poplar trees, their myriads of heart-shaped leaves rustling to the hot November wind, and sparkling like silver in the brilliant sunshine. More than that, I am, in that visionary moment, clinging fast to the slim vertical branches, high above the earth, forty or fifty feet perhaps; and just where I have ceased from climbing, in the cleft of a branch and against the white bark, I see the dainty little cup-shaped nest I have been seeking; and round my head, as I gaze down in it, delighted at the sight of the small pearly eggs it contains, flutter the black-headed, golden-winged siskins, uttering their long canary-like notes of solicitude. It all comes and goes like a flash of lightning, but the scene revealed, and the accompanying feeling, the complete recovery of a lost sensation, are wonderfully real. Nothing that we see or hear can thus restore the past. The sight of the poplar tree, the sound made by the wind in its summer foliage, the song of the golden-winged siskins when I meet with them in captivity, bring up many past scenes to my mind, and among others the picture I have described; but it is a picture only, until the fragrance of the poplar touches the nerve of smell, and then it is something more.

I have no doubt that my experience is similar to that of others, especially of those who have lived a rural life, and whose senses have been trained by an early-acquired habit of attention. When we read of Cuvier (and the same thing has been recorded of others), that the scent of some humble flower or weed, familiar to him in boyhood, would always affect him to tears, I presume that the poignant feeling of grief — grief, that is, for the loss of a vanished happiness — which ended in tears, succeeded to some such vivid representation of the past as I have described, and to the purely delightful recovery of a vanished sensation. Not only flowery and aromatic odours can produce this powerful effect; it is caused by any smell, not positively disagreeable, which may be in any way associated with a happy period in early or past life: the smell, for instance, of peat smoke, of a brewery, a tan yard, of cattle and sheep, and sheep-folds, of burning weeds, brush-wood, and charcoal; the dank smell of marshes, and the smell, “ancient and fish-like,” that clings about many seaside towns and villages; also the smell of the sea itself, and of decaying seaweed, and the dusty smell of rain in summer, and the smell of new-mown hay, and of stables and of freshly-ploughed ground, with so many others that every reader can add to the list from his own experience. Being so common a thing, it may be thought that I have dwelt too long on it. My excuse must be that some things are common without being familiar; also that some common things have not yet been explained.

Locke somewhere says that unless we refresh our mental pictures of what we have seen by looking again at their originals, they fade, and in the end are lost. Bain appears to have the same opinion, at all events he says: “The simplest impression that can be made, of taste, smell, touch, hearing, sight, needs repetition in order to endure of its own accord.” Probably it is a fact that when any scene, not yet lost by the memory, a house, let us say, is looked at again after a long interval, it does not, unless seen in a new setting, create a new image distinct from the old and faded one, but covers the former i............