In the meantime Nicolas Tolstoy was serving with the Russian artillery in the Caucasus; in 1851 he returned home on leave, perceived the danger of the immoral life his brother was leading, and persuaded Leo to join him. Tolstoy spent nearly three years in the Caucasus, and the fresh, beautiful and poetic life restored him to mental and physical health, and awoke in him both religious and creative power. His first novel, _Childhood_, appeared in 1852, and was at once recognised by leading Russian writers as a work of rare promise and charm. It is largely autobiographical, not in the actual incidents, but in the general circumstances, and especially in the mental development. It is most remarkable for the amazing psychological fidelity with which the impressions of childhood are remembered and recorded; the strong affections for parents and brothers, for sister and teacher, the awe-struck reverence for the crazy pilgrim, Grisha, the first faint gleam of romantic love, the poetry of forest rides, the love of animals, the shuddering physical horror in the face of death, the strange confusion and sadness of loss. Everything is at once realistic and full of romance; Tolstoy has brought before us all the clear-cut sharpness of these early impressions of the world before custom has laid upon them a hand "heavy as frost and deep almost as life." Tolstoy's life in the Caucasus, in its actual details, provided him with the subject-matter for two of his most fascinating works, _The Cossacks_, and _The Invaders_. These are not among his greatest productions; psychologically and dramatically they cannot equal the later novels, but they stand almost alone in their fresh, pure poetry. In these the remorseless realist shows himself as a romantic adventurer--almost, except for the deeper mentality, a Russian Stevenson; the breath of the mountain and forest, the clear, cold sweetness of dawn {21} blows through their pages; they charm with the sense of great spaces, of gay, glad daring; they are filled, above all, with the intoxication of freedom.