By means of bluish tints he painted the distant expanse of landscape. Mountains forming screens in the backgrounds and masses of trees lost in the distance, are all indicated by the azure tints which intervening layers of air give to remote objects. But as the foreground is approached, rightful colors begin to prevail and the azure tints are subtly graded, passing into a fresh and brilliant green amongst wooded declivities, and into the natural hue in the foliage of trees. Often heavy mists, spreading at the foot of high mountains, veil the outlines and still further emphasize the feeling of limitless space.[13] [13] I have not seen nor do I know of any paintings which can be said with certainty to be from the hand of Wang Wei. But from the records as well as from works directly inspired by him, an idea of his style and technique can be formed. Ancient paintings in _luo-ts'ing_ are found in Japan as well as in China. The British Museum of London has a scroll painted by Chao Mêng-fu, in the manner of Wang Wei, dated 1309. [Illustration: PLATE X. LANDSCAPE IN THE STYLE OF HSIA KUEI Sung Period. Collection of Martin White.] But when a master has carried his study of the fading of colors and of their relative values thus far, he must have considered not only the element of color itself, but also the collective tones which color is capable of expressing. From this to monochrome painting in Chinese ink is but a step; historical testimony shows that Wang Wei took this step. By the simple opposition of black and white, and through tone values and gradations of shades, he endeavored to create the same feeling of atmosphere and space which he had been able to express with _luo-ts'ing_. No original picture remains to inform us to what extent he succeeded, but by means of monochrome paintings of the Sung period which owe their inspiration to him, the importance of the reform accomplished, and the tendencies manifested in those lost works of art may be divined. Another master whose work can be defined with sufficient accuracy to cite as an illustration of a different aspect of the history of painting during the T'ang period, is Han Kan, who lived in the middle of the eighth century and who is celebrated as a painter of horses. The sculptured stones of the Han dynasty, especially the admirable bas-reliefs of the tomb of Chao-ling, representing the favorite coursers of the emperor T'ai-tsung, show the manner in which artists, from the third to the seventh centuries, were capable of studying and delineating the postures of the horse. It is therefore not surprising to find a great animal painter in the eighth century. Beyond question he was not the first. The written records have preserved the names of several of his predecessors and while the honor of having been the great founder of a school was attributed to him, it is possible that this refers only to an artistic movement bearing his name, of which he was not the sole representative.