Once more: “This is the difference between the mere botanist’s knowledge of plants and the great poet’s or painter’s knowledge of them. The one notes their distinctions for the sake of swelling his herbarium, the other that he may render them vehicles of expression and emotion. The one counts the stamens, affixes a name, and is content; the other observes every character of the plant’s color and form; considering each of its attributes as an element of expression, he seizes on its lines of grace or energy, rigidity or repose, notes the feebleness or the vigor, the serenity or tremulousness of its hues; observes its local habits, its love or fear of peculiar places, its nourishment or destruction by particular influences; he associates it in his mind with all the features of the situations it inhabits and the ministering agencies necessary to its support. Thenceforward the flower is to him a living creature, with histories written on its leaves and passions breathing in its motion. Its occurrence in his picture is no mere point of color, no meaningless spark of light. It is a voice rising from the earth, a new chord of the mind’s music, a necessary note in the harmony of his picture, contributing alike to its tenderness and its dignity, nor less to its loveliness and its truth.” If in the observation of Nature the ends which the poet has in view and the effects which he brings out are different from those aimed at by the man of science, not less distinct are the mental powers which each brings into play. The man of science investigates that he may reach rigid accuracy of fact, and this he does by the exercise of the dry understanding, and by the use of the analytic method. The poet contemplates the single objects or the vast spectacle of Nature, in order that he may discern the beauty that pervades both the parts and the whole, and that he may apprehend the intimations—the great thoughts, I might call them—which come to him through that beauty, and which make their appeal to the power of imaginative sympathy within him. Nature, whether in detail or as a whole, he regards in the relation it bears, whether of likeness or of contrast, to the soul, the emotions, and the destiny of man. But this relation he must seize, not by neglecting or setting aside facts, but by noting them with all the fidelity consistent with his main purpose. But it may be well to mark more definitely some of the ways in which the extension of natural science in modern times has reacted on the work of the poet.