He no longer imputed his feelings to Nature, and studied her influence on himself, but looked at her with impersonal interest. Weather, cloud, mountain formation, the species of stone, landscape, and social themes, were all treated almost systematically as so much diary memoranda for future use. There was no artistic treatment in such jottings; meteorology, botany, and geology weighed too heavily. The question, 'Is a place beautiful?' paled beside 'Is its soil clay?' 'Are its rocks quartz, chalk, or mica schist?' The problem of the archetypal plant was more absorbing than the finest groups of trees. The years of practical life at Weimar, and, above all, the ever-growing interest in science, were the chief factors in this change, which led him, as he said in his _Treatise on Granite_, from observation and description of the human heart, that part of creation which is the most youthful, varied, unstable, and destructible, to observation of that Son of Nature, which is the oldest, deepest, most stable, most indestructible. The enthusiastic subjective realism of stormy youth was replaced by the measured objective realism of ripe manhood. Hence the difference between his letters from Switzerland and those from Italy, where this inner metamorphosis was completed; as he said, 'Between Weimar and Palermo I have had many changes.' For all that, he revelled in the beauty of Italy. As he once said: It is natural to me to revere the great and beautiful willingly and with pleasure; and to develop this predisposition day by day and hour by hour by means of such glorious objects, is the most delightful feeling. The sea made a great impression upon him: I set out for the Lido...landed, and walked straight across the isthmus. I heard a loud hollow murmur--it was the sea! I soon saw it; it crested high against the shore as it retired, it was about noon and time of ebb. I have then at last seen the sea with my own eyes, and followed it on its beautiful bed, just as it quitted it. But further on he only remarks: 'The sea is a great sight.' Elsewhere, too, it is only noticed very shortly. Rome stimulated his mind to increased productiveness, and, partly for this reason, he could not assimilate all the new impressions which poured in upon him from without, from ruins, paintings, churches, palaces, the life of the people. He drew a great deal too; from Frascati he wrote (Nov. 15th, 1786): The country around is very pleasant; the village lies on the side of a hill, or rather of a mountain, and at every step the draughtsman comes upon the most glorious objects. The prospect is unbounded. Rome lies before you, and beyond it on the right is the sea, the mountains of Tivoli, and so on. In Rome itself (Feb. 2nd, 1787): Of the beauty of a walk through Rome by moonlight it is impossible to form a conception without having witnessed it. During Carnival (Feb. 21st):