A first cousin of St. Louis, Ferdinand III, the saint-conqueror of Seville and Cordova, donated to Chartres a window commemorating the patron of Spain. Three times was St. James honored here, so popular was the Santiago Compostela pilgrimage. St. Martin and St. Nicolas of Bari are also commemorated, the former some seven times, for it pleased the voyagers to noted shrines to record their travels. By pilgrimages French art and song spread in Italy and Spain. Single monumental figures of prophet or saint were used in the clearstory windows instead of small medallions, which would be indistinct when viewed at such a height. Although most of the windows in the cathedral belong to the XIII century, the XV century is represented in the Vendôme chapel, begun in 1417 by Louis de Bourbon, an ancestor of Henry IV. Much white was then employed for the better lighting of the church, and the straight saddle-bars of Suger's time were again made use of. No attempt was made for perspective in the earlier glass, which was treated like a translucent mosaic: relief was obtained by the skilled juxtaposition of tones. The old workers had taught themselves many of the secrets of optics. They knew that designs on a background of blue--an expansive color--should be larger than those on red--an absorbent. They knew that blue was a sedative, that red excited the vision, and that yellow stopped contours, hence it was to be employed in borders. It is not of technique that one thinks when standing face to face with the windows of Chartres. "Create in me a new heart, O God!" one murmurs when gazing at them. When at noon the sun renders the colors dazzling and bewildering, the cathedral seems to be chanting "_Sanctus! Sanctus! Sanctus!_" with the seraphim proclaiming that the whole earth is full of the glory of the Lord. Live coals from heaven's high altar are the windows of Chartres, then, cleansing us of our iniquities; and seeing with our eyes we see, and hearing with our ears we hear, and understanding with our heart we comprehend the vision and are converted and healed.