"The discovery of its antitype, this is the invisible and unattainable point to which love tends.... Hence in solitude, or in that state when we are surrounded by human beings, and yet they sympathize not with us, we love the flowers, and the grass, and the waters, and the sky. In the motions of the very leaves of spring, in the blue air, there is found a secret correspondence with our heart, that awakens the spirits to a dance of breathless rapture, and brings tears of mysterious tenderness to the eyes, like the enthusiasm of patriotic rapture, or the voice of one beloved singing to you alone." Yet this spirit, with which our later poetry is almost everywhere touched, "this mysterious analogy between human emotions and the phenomena of the world without us," as von Humboldt expresses it, in its present comprehensiveness is new to literature. To feel for mountains, forests, or the ocean, with mingled awe, love, and ecstasy, seems so natural to us, that we can hardly realize that Gray was striking a novel and significant chord when he wrote at the Grande Chartreuse, "One of the most solemn, the most romantic, and the most astonishing scenes.... Not a precipice, not a torrent, not a cliff, but is pregnant with religion and poetry." In Petrarch's letter we observe the deficiency in absorbing enthusiasm for the grander forms of nature, as well as his sense of the isolation of such sentiment from true spiritual life. Yet this letter is the most significant indication which we possess from the middle ages of a capacity for enjoying the sublimity of heights. In _Præterita_, Ruskin, while describing his eagerness at the first sight of the Alps, as a boy, has written two or three sentences that we may employ to illustrate the contrast between Petrarch and his predecessors: "Till Rousseau's time there had been no 'sentimental' love of nature ... St. Bernard of La Fontaine, looking out to Mont Blanc with his child's eyes, sees above Mont Blanc the Madonna; St. Bernard of Talloires, not the Lake of Annecy, but the dead between Martigny and Aosta. But for me, the Alps and their people were alike beautiful in their snow, and their humanity; and I wanted, neither for them nor myself, sight of any thrones in heaven but the rocks, or of any spirits in heaven but the clouds."