buildings, the bases of which are cut by a single straight line. Let us assume that they appear to be all the same size, and that you want to show that some are more distant than others, and represent them in a fairly dense atmosphere. You know that in such an atmosphere, the most distant objects, such as mountains, appear, because of the great quantity of air that lies between them and your eye, as blue as the air when the sun rises. You will therefore give the nearest building above the wall its real colour, and the more distant one you will make less distinct and bluer. And the one that you want to show even farther is that one you will make even bluer; and the one which lies five times more distant, make it five times bluer. And with this rule, it will be obvious which of the buildings that appear to be the same size is the more distant and so (in reality) larger than the others.

2. Vincent Van Gogh

Vincent Van Gogh, (March 30, 1853, -July 29, 1890), is generally considered the greatest Dutch painter and draughtsman after Rembrandt. He powerfully influenced the current of Expressionism in modern art. His uncle was a partner in the international firm of picture dealers Goupil and Co. and in 1869 van Gogh went to work in the branch at The Hague. In 1873 he was sent to the London branch and fell unsuccessfully in love with the daughter of the landlady. This was the first of several disastrous attempts to find happiness with a woman, and his unrequited passion affected him so badly that he was dismissed from his job. He returned to England in 1876 as an unpaid assistant at a school, and his experience of urban squalor awakened a religious zeal and a longing to serve his fellow men. His father was a Protestant pastor, and van Gogh first trained for the ministry, but he abandoned his studies in 1878 and went to work as a lay preacher among the impoverished miners of the grim Borinage district in Belgium. In his zeal he gave away his own worldly goods to the poor and was dismissed for his literal interpretation of Christ's teaching. He remained in the Borinage, suffering acute poverty and a spiritual crisis, until 1880, when he found that art was his vocation and the means by which he could bring consolation to humanity. From this time he worked at his new "mission" with single-minded frenzy, and although he often suffered from extreme poverty and